People will continue to do it because it's easier for newcomers to understand the races by comparing them to parallels that they are familiar with. No one who isn't familiar with Elder Scrolls lore is going to know what an Imperial is, but they probably know something about Romans. So when they see Imperials, they're naturally going to think "Romans".
I recall seeing MK (I think) expressing disdain about how other writers sort of "converted" Akavir into a fake Asia and how he never intended them to be like that.
That's pretty irrelevant, because in the end, it's whatever makes its way into the game that is the true cannon. So if the writers for the game say Akavir is Not-Asia, then it's not Asia.
The Akavri are kinda like Samurai
While what we've seen of the Akaviri seems to have a definite Japanese inspiration, with things like katanas and the like, I always assumed that Akavir is a combination of various Asian cultures, maybe Tseasci are pretty Japanese (As in like Samurai and all that, of course, not modern Japanese pop-culture) but the other Akaviri races are based on other Asian cultures, most likely, at least some sort of Chinese based race (Which is in itself a generalization, since with the size of what we now call China and its long history "Chinese" in this case can cover a pretty wide range of things. but since when looking for inspirations for fantasy races in real cultures writers tend to use the theme park version anyway, it works.)
All this being said, though, many Elder Scrolls cultures are definately based on real life ones, but they aren't necessarily based entirely on one culture, and beyond the obvious parallels like "Imperials = Romans", things tend to be a bit more subtle, and there's actually room for debate on exactly which culture's they're based on. And some of the completely fictional races are probably also in part based on stereotypical fantasy races, just played with a bit to make them seem less generic.
Of course, Cyrodiil has things like minotaurs, unicorns, and aloe vera, which kinda blows the alien environment for me a bit
Well, I agree, because I've seen lots of minotaurs and unicorns in real life, so it has that effect on me too.
But of course, seeing lots of elves running around never had the seem effect as seeing minotaurs and unicorns.