Would you kick over a wheelchair?

Why would you make fun of someone for what is clearly a mental illness?

Their mental illness may make them a bad person, I'll take your word for it since I avoid ragebait bullshit on the algorithm sites.

If all you do is make a lame trans joke with none of that context, you can't assume the audience has that context or will see you as anything other than a bully doing a drive by sucker punch. You aren't one upping anyone. You just give them more attention and join them in the muck.