There's a difference between not caring about someone's sexuality, and "dont ask dont tell". Prejudice still exists today, because for some reason, we as society feel a need to make everyone's differences front page news, or a ticker-tape parade, or a half-hour tv program.. Things that if equality was really important, wouldnt matter in the slightest.
Im not proud of someone for "coming out of the closet", Im proud of them for accepting themselves, and being themselves because thats what makes them happy. The only reason I can ever think of to have to come out and say "Im gay" or "Im straight" is because you just got hit on by someone, and you need to tell them why its not your cup of tea.