I am relatively new to social media and being homebound due to age/illness, don't get out to socialize much.

So its been very shocking to see/experience all the constant use of profanity from younger ppl online.

I left Reddit bc it was just too overwhelming.

My parents raised me to speak properly. They raised me to understand that ppl who use constant profanity are using it as a replacement for a poor vocabulary. Its constant use also brings a feeling of possible physical violence, so I avoid ppl who use it repeatedly.

When did this start, and why? I would never hire someone who speaks like that.

It's just a vice of the times, unfortunately. I used to talk like that too, and I have many relatives, acquaintances and coworkers who do as well.

Here's what St. Alphonsus had to say on the matter:

ON THE VICE OF SPEAKING IMMODESTLY.
“He touched his tongue, …. and the string of his tongue was loosed.” MARK vii. 33, 35.

IN this day’s gospel St. Mark relates tlie miracle which our Saviour wrought in healing the man that was dumb by barely touching his tongue. “He touched his tongue and the string of his tongue was loosed.” From the last words we may infer that the man was not entirely dumb, but that his tongue was not free, or that his articulation was not distinct.
Hence St. Mark tells us, that after the miracle he spoke right. Let us make the application to ourselves. The dumb man stood in need of a miracle to loose his tongue, and to take away the impediment under which he laboured. But how many are there on whom God would confer a great grace, if he bound their tongues, that they might cease to speak immodestly! This vice does great injury to others. Secondly, it does great injury to themselves. These shall be the two points of this sermon ...

9. Be attentive, then, my brethren, and guard your selves against speaking immodestly, more than you would against death. Listen to the advice of the Holy Ghost: ”Make a balance for thy words, and a just bridle for thy mouth; and take heed lest thou slip with thy tongue and thy fall be incurable unto death.” (Eccl. xxvhi. 29, 30.)
”Make a balance” you must weigh your words before you utter them and”a bridle for thy mouth” when immodest words come to the tongue, you must suppress them; otherwise, by uttering them, you shall inflict on your own soul, and on the souls of others, a mortal and incurable wound. God has given you the tongue, not to offend him, but to praise and bless him.
”But, ” says St. Paul, “fornication and all uncleanness, let it not so much as be named among you, as becometh saints.” (Ephes. v. 3.) Mark the words”all uncleanness. ” We must not only abstain from obscene language and from every word of double meaning spoken in jest, but also from every improper word unbecoming a saint that is, a Christian. It is necessary to remark, that words of double meaning sometimes do greater evil than open obscenity, because the art with which they are spoken makes a deeper impression on, the mind.
10. Reflect, says St. Augustine, that your mouths are the mouths of Christians, which Jesus Christ has so often entered in the holy communion. Hence, you ought to have a horror of uttering all unchaste words, which are a diabolical poison. ”See, brethren, if it be just that, from the mouths of Christians, which the body of Christ enters, an immodest song, like diabolical poison, should proceed.” (Serm. xv., de Temp.) St. Paul says, that the language of a Christian should be always seasoned with salt. ”Let your speech be always in grace, seasoned with salt. ”(Col. iv. 6.)

Our conversation should be seasoned with words calculated to excite others not to offend, but to love God. ”Happy the tongue,” says St. Bernard, ”that knows only how to speak of holy things!”

Happy the tongue that knows only how to speak of God! brethren, be careful not only to abstain from all obscene language, but to avoid, as you would a plague, those who speak immodestly. When you hear any one begin to utter obscene words, follow the advice of the Holy Ghost: ”Hedge in thy ears with thorns: hear not a wicked tongue.” (Eccl. xxviii. 28.)

“Hedge in thy ears with thorns” that is, reprove with zeal the man who speaks obscenely; at least turn away your face, and show that you hate such language. Let us not be ashamed to appear to be followers of Jesus Christ, unless we wish Jesus Christ to be ashamed to bring us with him into Paradise"

I remember when frequent use of foul language started in school, by some of my friends’ parents, and by people in public. It was in 1967-1968 when I was aged 10-11.  My mother and grandmother told me the same thing as JOAN’s parents.  Bad language, whether blasphemy, profanity, or vulgarity is used by those unable or unwilling to properly express themselves.  
It wasn’t tolerated in my home, not by we children or by our friends, or by adults.  If we children used holy names in vain or uttered profanity, the punishment was to taste the top of the Palmolive (dish soap) bottle, say or write the Act of Contrition a number of times, and if below puberty, get our age in swats to the derrière.  If older, then another physical punishment, usually performing vigorous exercises for one's age in minutes.  For vulgarity, we still had to taste Mrs. Palmolive, and then think of and repeat or write more appropriate words.  Example, “derrière, bottom, were acceptable, “butt, ass, were not!  
Of course, most of us tested the limits from time to time, myself included.  I didn’t often get severely punished, but once, while on a road trip with our Nimrod tent trailer, our car, a blue Dodge station wagon, broke down on I-40 outside of Nashville, TN.  It failed to shift properly and the rear brakes kept sticking. Dad pulled into the far end of a Sears parking lot, set up the trailer, and we stayed the night.  First thing in the morning he limped off in the car to a garage, leaving Mom and us in the trailer.  There were no trees anywhere, so as the sun rose, the trailer got hotter and hotter until it was intolerable.  The baby vomited from overheating, so Mom gathered us up and we set off across the huge lot for the air-conditioned Sears.  All was well while we looked at everything there was to see, but after a time boredom set in.  Mom bought dresses for we girls, and toy trucks for the boys.  Then we went outside and tried to play on the sidewalk where the building cast a little shade.  It was still too hot, so back inside we went with the idea to go through the store finding something that started with each letter of the alphabet, a good idea in theory, but not in practice with seven kids.  We either got too excited or bored.  We began playing on the escalator, running, hiding in clothes racks, and my youngest sister, age four, had a “meltdown.”  Mom gathered us up and we were already being herded towards the door when the manager “invited us to leave.”  Halfway across the broiling asphalt, I could feel the heat through the soles of my sneakers.  Everyone was cranky and Mom had a migraine.  I looked up and realized I’d fallen behind and ran to catch up, all out of breath, grumbling that my feet were burning up.  Mom asked me why the bad attitude.  I replied, “ ‘Cause it’s so G__ d___ hot, you can fry a f____g egg on the sh___y sidewalk!”
My mother was shocked and said, “Would you care to repeat that, young lady?”  So I did.
Let’s just say I got a good taste of Mrs. Palmolive, got writer’s cramp from four pages of the Act of Contrition, and my bottom strapped by Dad upon his return.  Next day, we left, the car repaired, but not before finding a church where Dad knocked on the rectory door and arranged for me to go to Confession!  I was very embarrassed and wanted to wait until Saturday to find a priest, but Dad knew what was needed.  I remember the priest who came out of the door was ancient and amazingly skinny.  He looked healthy enough, but I’d never seen anyone so thin and straight. Even Dad remarked on his physic.  None of us, Dad included, could remember his name except that it was something Irish. We referred to him as Fr. O’Pencil!  He was an excellent confessor, that I remember.  The name of the church was St. Patrick’s.  I’m sure he’s gone to his reward.  RIP, Fr. O’Pencil.

I am relatively new to social media and being homebound due to age/illness, don't get out to socialize much.

So its been very shocking to see/experience all the constant use of profanity from younger ppl online.

I left Reddit bc it was just too overwhelming.

My parents raised me to speak properly. They raised me to understand that ppl who use constant profanity are using it as a replacement for a poor vocabulary. Its constant use also brings a feeling of possible physical violence, so I avoid ppl who use it repeatedly.

When did this start, and why? I would never hire someone who speaks like that.

I hate it too. It amazes me how many Catholics also write things like that and you see it even on this website.

Apparently the younger generations, for example the liberals on Reddit, use cuss words to give credence and force to their words.

Which makes sense, as their whole worldview is based on emotion. If they are emotional, they are being genuine/sincere and their words are more likely to be true -- again, according to their worldview.

Example:

"Trump should be put to death for inciting an ιnѕυrrєcтισn on January 6th, 2021."

Not convincing: "I agree."
Much more convincing: "F***ing this."

I don't think I saved it off, but someone did a nice paragraph explaining this -- it resonated with me and it was very convincing. He had better examples and explanation.

Suffice to say, they throw around especially the F-bomb as a way to make their words more emphatic.

Kind of like having 3 witnesses with you, so that every word you say is underlined and seconded by those 3 people -- giving your words more gravitas and weight.

It's not rational, but with human beings it DOES work, even on me.

Let's face it -- if someone says "This hamburger isn't very good." you would just ignore them. But if someone threw a fit, screaming "THIS HAMBURGER IS F***ING HORRIBLE! and started spitting and coughing, you might be tempted to eat somewhere else -- just in case there's some fire behind all that smoke. That's what I'm talking about.

I agree, that the F-word has become an "emphatic" rather than the original sense.  Still gross and vulgar, but something is not awesome unless it's f***ing awesome ... so an emphatic even when intended in a good sense (here emphasizing "awesome").