Organically meeting someone at a party or the like is simply super rare in the kingdom of gay. Say it's stereotypical, but there are a few things almost every gay dude watches. Other queer-centric shows like American Horror Story and (much to my chagrin) Sex and the City are examples.
As such, the two of you are going to have a mildly-to-very awkward hello. Usually you can find some prerequisite "gay" show (quotes because I think the idea of a gay show is actually ridiculous) to dish about.
He may be making himself good for the other man in his life!
It's just..coming out stories are super heavy and emotional.
Some guys haven't even come out despite them going on dates, which makes a whole other mess of awkward.
Otherwise you can use their list to pretty much judge the other guy's entire character.
Note: if you want my panties to drop, just mention Buffy.
Coming out to your family and friends is the one experience almost every gay guy can share, so it sparks a conversation both of you can relate to.