***If Higgins were attempting to imitate the accent of Kaparthy at this point, it would mean that the foreigner learned his English in America ("where they haven't used it in years!). But then why would Higgins pick up on this most unusual accenting of Kaparthy when there is no evidence of such a peculiarity in the scenes in which the man himself appears?*****
Not only that, but even if Karpathy were attempting to pronounce "aren't" in the American English way, he'd still be mispronouncing it by leaving off the "t" at the end -- and since it is hammered home to us that Karpathy himself is a stickler for correct pronunciation, that would NEVER happen. I'm sure Lerner self-justified "aren" as an attempt to make fun of Karpathy's pronunciation, but again, that makes zero sense for that character.
****But like so many, none of these matters prevent me from loving the whole glorious show, which just goes to prove that humans can love the imperfect sometimes with even more zeal than the perfect ... if we ever find such a thing.***
EXACTLY. As I've noted elsewhere, it really bothers me when people who love a show, film, etc. can't recognize and discuss its flaws while still loving it -- and, conversely, when people who despise a show, film, etc. can't acknowledge what might be good in it.