It can be annoying when typing in a Cyrillic-based language (and presumably other alphabets), especially when it's not your native language. It's also rather annoying for kids who are learning to type.

Just saying, as an ex-n900 user, that niche market is much smaller than we think. I wouldn't go back to a n900 equivalent today. Typing accents in French or non-latin characters was pretty annoying.