What most people believe about the "Mandela effect" is that it's evidence of other dimensions -- close to our own world, but NOT QUITE. Have you ever heard people throw around the phrase "this timeline..." as in, "I hate this timeline." -- that's what they're talking about. Time travel and/or travel between "parallel universes". It makes for great sci-fi, and I enjoy such shows/books personally, but it's COMPLETE FANTASY.

For that matter, Deja Vu is offered as evidence for Reincarnation.

Which is why you have to be on your toes to downplay these phenomena, if you wish to fight error in all its forms. Personally, I think the Mandela effect is stupid. It's basically "One human being can be wrong...but if a billion people are wrong, it's spooky." Why? Humans are always wrong about stuff. Multiply by a billion, now you have a BILLION people that think Mr. Peanut oops I mean the Monopoly Man, had a monocle. So what? Humans are wrong all the time. Why not a bunch of them en-masse?

People think Fruit of the Loom had a horn (think: cornucopia) as well as a pile of fruit. Well, the two USUALLY go together, so people basically REMEMBER IT WRONG. Human memories are notoriously bad and unreliable. They say that every time you access a memory, you RE-WRITE to that spot in your brain, with slight differences. So your memory literally changes every time you recall it!

And in this age of mass media and mass programming, OF COURSE people are going to share the same ideas, both true and false. It's basic psychology. If I lead your mind with a few key phrases (or nouns), I can get 99% of people to think the same "next word". Mentalists do this kind of thing all the time, and make a living off it.

now you have a BILLION people that think Mr. Peanut had a monocle

You mean he doesn't?

I'm pretty sure he does have a monocle

Perhaps Matthew is suffering from reverse or double Mandela effect.

https://www.urbo.com/content/the-monopoly-guy-never-had-a-monocle-and-7-other-lies-we-all-believe/

Matthew read that article and got confused over the Jiffy/Jif peanut butter thing and the Monopoly guy thing.  Mandela effect in action.

Because, again, it doesn't matter.

I'll edit my post above if it makes you all feel better.

So you do think it matters

A situation like this is the stuff that inspires satire!

Allow me to demonstrate. Here is my impression of this thread:

(NOTE: THIS IS A WORK OF FICTION. NOTHING IS BEING IMPLIED ABOUT ANY REAL PERSONS.)

Matthew: I just saw Fr. Pagliarani, dressed up as Frankenstein, get arrested by a team of FBI officers. Here's a photo I took of the event! This is huge.

CathInfo Member #1: "Matthew, Frankenstein is the doctor."
CathInfo Member #2: "Yeah, #1 is right. Frankenstein is the doctor, not the famous monster with the neck bolts."
CathInfo Member #3: "I thought there was something funny. Yeah, I doubt Dr. Frankenstein would do anything to get arrested! hahaha"
CathInfo Member #4: "Dr. Frankenstein knows that E revolves around S."
CathInfo Member #5: "Frankenstein is the doctor, not the monster."
Etc.

Now tell me, how would YOU react?

If you're honest, you'll admit that you'd scream, "HELLO!? Who cares about the monster's name. Enough already! What about Fr. Pagliarani getting arrested? Why was he wearing a monster costume?"

When I first heard about the "Mandela effect", my first thought was, "What?  What idiot though Mandela died in prison?  He ran South Africa into the ground!"

To this day, the only examples of the "Mandela effect" those who created the term use are in advertising and very, very unimportant issues.  I have never figured out what the big deal is except that I have heard what Matthew pointed out.  Ancient Aliens kind of people do suggest that it is evidence of multi-dimensions that somehow crossed into our dimension.  The only purpose of that I can imagine off the top of my head is to re-enforce modern people's unbelief in the True God.