why can't you enjoy Europe as a place where people treat you well?

Your idea of rationale behind this is complete nonsense (hello, Sadkov!)

there are several practical reasons to prevent otherwise physically healthy people from transitioning.

first, some of such patients simply need good mental care
second, their ideas of mutilating their own bodies is nothing public healthcare system is supposed to pay for or deal with the consequences of;
third, as healthcare is public, they have no other options.

The same applies to plastic surgery without having an underlying medical condition (traumas, skin burns etc). Like somebody got surgery to increase tit size and then things went wrong and they eventually became patients of the general public healthcare.

personally I have nothing against adults transitioning or doing plastic surgery and believe they can serve as guinea pigs, test animals for these type of treatment. If they can give consent of course, that is, no transitioning for minors or mentally immature under any circumstances.

so the only thing you actually need is to stop bullying in schools. that's okay. much better than pushing random meds down one's throat.

Bullying in school is physical violence. Gatekeeping is something else.