MY personal guess is because a lot of the trans people that are encountered here are the weirdos we talk about, and when you're mostly exposed to a bunch of freaks, you assume that EVERYONE is like that. And I'm guessing for some of the people here, that's their first encounter with trans people.
My first and main encounters though with trans people were generally normal, average everyday people who just happened to be trans, so my impression seems to be that most are just like everyone else, it's just the ones who get attentoin are duh, the freaks.
Let's face it, who do you want to talk about? Trans dude goes to the grocery store, buys milk, comes home and watches TV? Or Trans dude goes to the grocery store, freaks out because the tampons are labeled "women's hygiene" rather than "people's hygiene", screams at some innocent teenage clerk, etc?
Or the activist who wants trans people NOT to be fired from their jobs because they happened to be trans, vs. people like Riley, who claim that excluding trans people from your dating pool is bigotted?
Quite frankly, I don't know what you expect people to do if they're trans. It's not really fair, I think, to expect people to suffer in silence, and dysphoria really does exist, from the people I've talked to. And honestly, none of these people are hurting me, so why should I give a shit? The thing is, I suspect a LOT of these lolcows would be lolcows even if they weren't trans -- if you want proof, look no further than the original, Christian Weston Chandler. Do we honestly think that Riley would be any less of an obnoxious scold if she were cis?
Same as anyone. It's always the obnoxious assholes you hear about, so you suspect EVERYONE'S like that. Because that's what's entertaining. So Is suspect the freaks tend to ruin it for everyone, just like they do in any catagory of people. That's how it's always been, since the beginning of time.
That's just my observation. YMMV