Hm. As someone who is both gay and a practising Christian, I'm not convinced it's quite as clearcut as you're making it. I can imagine a situation where a homophobic or anti-religious workplace could suggest that I was giving too much information and creating a hostile environment for my colleagues if someone asked me what I did over the weekend and I told them I went to a gay club on Friday night and to church on Sunday.

Proselytising isn't appropriate in the workplace, and nor is sexual harassment. But I don't think the difference between unacceptable proselytising and manifesting one's religious beliefs in the workplace is necessarily as clear as you're claiming it is here.