It's from wikipedia but that list doesn't take much into account as there's no way to determine if they are leading roles, supporting roles, reoccurring roles, guest roles, or reality tv characters.
You also have to consider that they might not all be roles for American television shows- some asian tv shows marketed to women sometimes have a whole cast of gay characters and a Brazilian show has 4-5 possibly bisexual males that kiss once or twice.
It also lists characters that might or might not be gay.
My favorite is when they introduce a gay (usually male) character only to kill him off an episode later.
Furthermore, not all those shows call for a 25-35 year old (muscular) actor.
So, unless you're buddy-buddy with Ryan Murphy or come from a wealthy family, no actor can sustain himself by only taking on gay roles because it is extremely limiting.
...but if he fails...He might jump on the OF bandwagon possible win-win for us.