It's clear that it's people just mad they aren't getting the ship they wanted so they are picking apart an actual canon one.
I think some of it is homophobia too. But really, Buck had the bad day and he started the flirting. Getting to know someone isn't linear.
I recall some people saying Tommy was a bad guy for leaving Buck outside of the restaurant after their first date. As if Buck were a three year old left unattended and not a grown man who lives and works in LA and knows how to hail a taxi or call an Uber.
Ha. My favorite argument is that he tried to out Buck. Eddie and Marisol were talking about closets. There's no way they would have picked up on it. Buck's comment was stranger.