Unironically, my brother had a CO in the navy who was accused of racism.
He was aquitted on grounds of generalized misanthropy. He hated everyone, but equally.
On a more serious note, you're exactly right. People need to be held to account for behaviors they control.
Race? Gender? Orientation? No real choice in that, ignore it.
But everyone's got an ***hole, just wish they'd stop showing it. It's frustrating, because I have trans friends. I want them to get the care, love, and respect they deserve as human beings.
Defending this sort of behavior hurts that. It makes people cautious, then frustrated, then angry. I'm convinced some of the 'hateful' people I've seen aren't even hateful, they're just tired of that eggshell walk. They want it to go away, and they're tired. It's the verbal equivalent of an exhausted, overstimulated cat swatting at you because it wants rest.
Anyone who genuinely supports LGBTQ stuff needs to be the first person to disavow malicious behavior, and hold these people to account. If malicious behavior is allowed to become associated with who you're trying to help, well... one must imagine Sisyphus happy, I suppose.