While in the strictest definition of proud this could be conceived as correct, although the definition starts with proud of one's accomplishments, it finishes with proud of what ones own qualities. But on even a cursory glance at some of the literature around the pride movement the error is quickly found. Just as some people aren't proud for being an atheist, skeptical or human, people aren't proud for being Gay in the strict definition of the term, or for that matter proud for being anywhere else in the sexual spectrum.
They are proud for coming to terms with it in a predominantly heterosexual, binary gendered society, they are proud for coming out in such a hostile environment to not only gain support from non-LGBTI people but to make it easier for others to come out. This kind of pride sounds really familiar, oh wait a minute these are the same arguments for coming out as an atheist, for having the reason rally, or any number of Celebrations of reason etc.
I agree with Boghossians premise, to quote a great philosopher that came before him "In all affairs it's a healthy thing now and then to hang a question mark on the things you have long taken for granted." - Bertrand Russell
But I think Boghossian may have missed the mark on this one, and in doing so has gotten off side a large part of the community that would invariably be opposed to some of the same things he is opposed to, yes you can be LGBTI and religious, but I think if you do you have a short and forgiving memory for the persecution you suffered under religious hands.
Greta Christiana writes a more thorough refutation here.