[wiether]

> non-native English speakers

As one of them, I can tell that I agree with @NiloCK.

Maybe because I'm French so I had to learn even stronger rules, but to me if someone doesn't capitalize proper nouns in English, I'll first think that I misunderstood what they were writing because of my deficiencies, before coming to the conclusion that they didn't capitalize.

Whereas, in French, I'm confident enough to mentally capitalize without even thinking about it.