Other than (killing or) harrassing no one has been bothering ... ??

Just how blindly dismissive can a single comment get?

I'm not on any tran bandwagon but it's plain they've been persecuted in western culture for centuries to date.

This comment clearly comes from a place of ignorance. This attitude is part of the problem too. You just need to listen to them and they can tell you all they ways that people have been bothering them. Just because you can’t conceptualize how life can be hard when you have an incongruity between your physical body and mental self, it doesn’t mean that you can hand wave away other people’s struggles with this attitude of “ahhh they’re fine no one’s bothering them”. Shift your perspective to see the problem

Ah, they're not trans now. They're "cross dressers"

You're very much arguing in good faith already :)