Once upon a time I didn't know any of this stuff.
Then I learned it.
And eventually I realized that, as far as D&D is concerned, I just don't care.
Which is fine, and which is why I described this as a peeve rather than any sort of serious advice on how you or anyone else should play their game. I have that sort of advice too, but whether you want to have studded leather in your game or not is something
I just don't care about.
However, I do care about believability and coherency and so forth, and if you truly don't care - that is, if you really have no positive preference for studded leather - then whether it goes away in favor of ring armor or something more sensibly constructed or some other more historical sort of armor in the same slot should just cause you - I would think - to shrug and go with it. Or in short, while you don't see the harm in having it (which I understand) there are some people who seem oddly to see harm in leaving it out (which I don't understand).
I have absolutely no understanding of the argument that says, "This fantastic thing is in the game. Therefore it doesn't matter what is in the game." To me that might as well be like saying, "Build the doghouse out of pancakes, because wheels aren't square." One thing doesn't imply the other. It's just nonsense. And I'm inclined to think that anyone who advances that argument hasn't thought it through very well, and doesn't in fact live by its implications. Rather, what they actually believe and live by is that certain things "go together" as part of the trope, and they willingly suspend belief for those things that they see as naturally or logically belonging together - like fire-breathing dragons, dinosaurs, and Thor. At some point, they'd go, "That's too gonzo for me." or have some similar sort of reaction, when their suspension of disbelief got broken.
For me, it's not even merely suspension of disbelief involved, but 9 college hours of medieval history and plenty of time in the library reading about this sort of thing for fun. The real actual motivation is not "realism" as they suppose, but that things that are real - or are inspired by what is real - tend also to be richer and more satisfying than what most people can just make up on their own. The same is true of even of real world myths. There is just more cool cultural baggage that is going to come along with fire-breathing dragons, dinosaurs, and Norse Gods than any skoowzles and flumbungs that you make up. In literature, this technique is called 'allusion'. By grounding my game in things that are real I'm with easy labor dragging a whole world of coolness into the game, just like fire-breathing dragons do. The fact that "studded leather" has kinda taken on a life of its own, becoming a fantastic trope in its own right, is the big reason why I don't care one way or the other if it appears in your game. But by not having it in my game, I'm instead pulling into my game allusions to historical martial arts and culture, that to me are more powerful and interesting than anything that has yet evolved around the idea of "studded leather". You might not know that they are there, but I do - which is why it matters to me.