The 2 main issues I have with troon bullshit are: -
1. Irreversible damage being done to people (especially kids/teens) via puberty blockers, hormones, and surgery. Troons lie about this all the time. They claim that puberty blockers cause no lasting damage and are fully reversible. They say that nobody is carrying out surgery on people under 18. When it comes to people who desist or who detransition, they will simply say "they were never trans anyway!", which is all very convenient.
2. Erosion of sex-based rights. We're already seeing a bunch of examples of that. Men winning prizes in female-only categories. Men in female changing rooms and bathrooms.
There are no issues like this with homosexuality. That's why such comparisons are utter nonsense.
On a fundamental level, the troon argument is a confused, ever-changing, inconsistent mess; more like the product of a religious cult than consistent, clear principles and arguments. I'm being asked to believe things that I know are false, both to the detriment of (especially) young people's health, and sex-based rights that were hard fought for.
Conversely, with gay rights, there's no experimenting on kids with drugs. No chopping off of teen girls' tits. No sports advantages. It's solely about sexual attraction and same sex attracted folks being treated with respect.