Perhaps not in your native language.
Note that I share the same native language with moritz who made the initial point. Since he shares your view, native language doesn't seem to be the dividing line
"Proper capitalization in programming is vital..."
Sure, and proper capitalization in sign language is absolutely non-vital. If you want to offer programming languages as analogy I might ask where the for loop is in the english language ;-)
Don't get me wrong, I've got nothing against keeping perl in lowercase. But whatever importance you or I might attach to it, the question is what impression newcomers take away when they get corrected for that. Look at young programmers used to twitter and the World-of-Warcraft chat and guess what they think about the importance of case