Problem is, how do you tell that character X is indeed character X and not something that looks like character X?
Further, how far do we take the function names are a language thing? Should an ss be rendered differently in Germany? Is leß() the same as less()?
So yes I don't mind non ASCII characters, I'm not sure this should primarily be about supporting users of foreign languages, rather to increase the number of characters.
Although at this point, I would guess that most programmers have some kind of ASCII compatible keyboard? So what's being gained by having characters that aren't on that keyboard?