Why do you mind their existence? These people are doing stuff to themselves because they are in pain and trouble, Buck Angel for instance has been very open about the downsides of taking male hormones leading to vaginal atrophy due to testosterone intake, how can you say it promotes being trans?
You're just being hateful.

That's a weird question. Why would you oppose the entire practice of doctors giving medications and surgeries that cause serious, chronic issues to people with serious mental issues that asked for them? The answer ought to be obvious. Plenty of them are bothering people plenty with all the invading single-sex spaces and violating peoples' rights to safety and privacy in that way, and they're bothering people by recruiting ill children into their cult and making them lifelong medical patients. But even besides that, doctors shouldn't do you harm just because you ask them to.

These people are not doing things to themselves. These people are having doctors do things to them, things that are unethical and harmful, and they're lobbying politically for everyone to have access to medicalized self-harm. Nobody minds them "existing." People mind them promoting and lobbying for nonsense pseudoscience. IF they stop doing that, nobody will mind them existing at all.