I don't have any particular problems with retcons like that when things are left relatively ambiguous, but saying that the Rawhide Kid was gay when here he is head over heels in love with a girl and agonizing over how to break up with her is just ignoring the original source material - and that ain't cool. I have no problem with a gay cowboy, but they should've picked someone who actually might have BEEN gay, not someone who was clearly heterosexual.