I don't think that's true of all trans people, but - anecdotally, as with many comments I make on here - several trans people I've met have been the type where being trans is their entire identity, as in it's the only real defining characteristic about them that they show. Obviously the majority are likely not like this, but those few who are seem to be the vocal ones as well.

Okay, I don't feel this way either. Unfortunately, most of the world is not as liberal as the community on hacker news, and as soon as you mention 'gay' or 'transgender', the discussion turns to gender / sexual orientation rather than the original topic at hand. The article sidesteps this issue by not mentioning it until much later, that is all.