The Catholic prelates have the right to set the dress code for their church/chapel/institution. The Vatican has a dress code for women. If you show up at the Vatican inappropriately dressed they will not let you enter.  

In general the principles are that our clothing should express our respect for the Holy Mass and should also be in conformity with the dignity of the Holy Sacrifice and our dignity as temples of the Holy Spirit ... and of course this might vary from culture to culture, and could be different for very poor regions, etc.

Male clothing should be the best that we have ... unless there are practical reasons one can't.  So, for instance, if I work as a laborer and want to assist at a daily Mass before I go to work.  That's where the term "Sunday best" comes from.  Male clothing should be modest and dignified, respectful of the Mass.  "Best that we have" might vary around the world, as there are some people too poor to afford elegant clothing ... or even shoes; my dad told me that, as a child, he served Mass bare footed because his family could not afford shoes.

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Miseremini: That is a parable!

 or whatever they deem most comfortable and suitable to the weather conditions regardless of the fashion of the day.

Yes and Christ taught in parables!!!!!
So you think your clothing should be for your own comfort and suitable to the weather.....well what about the priest?  What kind of vestments should he wear for his comfort and the weather?
Clothing should be suited to the occasion and in North America a suit and tie are still representative of best.

Some totally miss the point; "this might vary from culture to culture" and "according to your culture of dress" is exactly the question of the post. Is there any magisterial declaration that compels men to abide by the current fashion of the region in which one goes to church?

Nadir: "Does that make sense?" No, why is it acceptable for women but not for men to wear skirts or clothes that reach between the knees and ankles? Although that is not the point, I have seen people changing right after Mass (e.g. men putting on jeans, women putting on pants) which is a whole other issue of hypocrisy.
Miseremini: That is a parable! On the contrary, I see diplomats and influencers wearing all sorts of clothes before dignitaries, not just suits and ties.

Since nobody has yet cited any authoritative source, I am inclined to believe that specific mandates such as "suit and tie" are non-binding personal opinions which should not even be posted to avoid scandalizing someone who wants to go to Mass wearing their thaub, kilt, lederhosen, caftan or whatever they deem most comfortable and suitable to the weather conditions regardless of the fashion of the day.

There's no legislation, but common sense suggests abiding by the customary dress of a place (if possible) ... if for no other reason than not to create a distraction.  So, for instance, a Scottish man should not show up to Mass in the U.S. wearing a kilt (vs. suite and tie), since that would distract people from prayer.  Non-distraction is another principle of dress at Mass.  So, for instance, don't wear a shirt that has some kind of written message on it.  Don't wear extremely loud colors, etc.  These things cause a distraction.

There's probably a hierarchy of prudential considerations, with modesty being #1.

#1) Modesty
#2) Cleanliness
#3) Non-distraction
#4) Dignity (the best you can muster given your means)

I would put them in that order, but others may differ.

Since nobody has yet cited any authoritative source, I am inclined to believe that specific mandates such as "suit and tie" are non-binding personal opinions which should not even be posted to avoid scandalizing someone who wants to go to Mass wearing their thaub, kilt, lederhosen, caftan or whatever they deem most comfortable and suitable to the weather conditions regardless of the fashion of the day.

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No, that isn't right at all.  What you're doing here is identifying a lack of a universal and from that concluding that just about anything goes.
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It is a general principle of charity that our mass attendance be non-disruptive to our fellow attendees.  For that reason, you will find clergy building things like quiet rooms for parents with especially unruly children even though there's no Church law or universal legislation that establishes the decibel point at which a child must be removed from the Church.  Ditto, you will see recommended dress codes.  
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You call it a scandalous personal opinion, when in point of fact it is merely the application of common sense strategies to help provide an appropriate worship environment.  Is it appropriate, if I'm a diabetic, to, as a matter of course, inject insulin in the pew?  Is it appropriate, if I am a doctor, to have my pager on the loudest volume during mass (as opposed to vibrate)? No, it isn't.  And it doesn't have anything to do with it being sinful to take insulin or be a doctor, it has everything to do with the general principle of charity which insists that we not be disruptive to our neighbor.  
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Does that mean that a diabetic can't, if emergency calls, use their insulin right there in the pew? Of course not.  Nor does it mean that men can't show up to mass after getting off a long shift and wearing jeans.  What it does mean, at the very least, is that these kinds of things remain exceptional and out of the ordinary.  You showing up to mass every Sunday in something culturally disruptive like a kilt or lederhosen is what the scandal would be.  Because such dress is culturally alien, you would be signalling your disregard for your parishioners and your own vanity.

Do you come from the NO? I ask this completely non-prejudicially because I grew up in it, but I feel like I can relate to your issue here because of that perspective. As a kid, my idea of a Protestant "mass" was from the Simpsons where they're all very well dressed in suits and ties, slicked back hair, etc., whereas at my own Catholic Masses people were dressed far more casually(not completely casually - except for the youth - but wearing jumpers instead of suit jackets, etc.). So I associated "over-dressing" with, as you said, "Anglophile Protestantism".

But if you look back to the time before Vatican 2, people wore suits even just going around their business in town. People valued dressing well at all times, so of course they did so for Mass. And if you look at old photos, you'll see that reflected. For example, here's an urban church in Ireland in the 1950s:



All the men are wearing suits and ties under their coats. So clearly dressing really well for Mass isn't "Anglophile Protestantism" as we thought. Now, of course, fashions and dress styles change down the centuries. But the point is to dress well and dress respectably. And yes, fashion may be subjective, but to avoid causing scandal it is always best to follow the old adage: "When in Rome, do as the Romans do". Even if dressing a certain way is the norm where you're from, if a different way is the norm in the parish you're going to, you should probably follow suit(unless the "norm" in that parish is objectively immodest, in which case that priest has a lot of work on his hands).