Is it not fair to assume that reassignment surgery, which effectively destroys the reproductive system, is something which negatively affects someone's normal function? I'd like to believe that there's some sort of middle ground between stigmatizing and enabling. To me, surgery seems to be more of an enabler.
well no, keeping the same pair of genitalia doesn't really do much improve psychological health if you're experiencing severe enough dysphoria. i'm not sure what you mean when you say there's a relationship between stigma and enabling though. people getting treatment doesn't mean that we're playing into their delusions, it means they're making choices to improve their own lives by reducing the negative effects of their psychological problems. they should be able to do that free of stigma. the assertion that these treatments are enabling seems to also dismiss GID as a legitimate problem; it says that their symptoms aren't real enough to warrant action, and that would be highly inappropriate in any medical context.
and regardless, reassignment surgery isn't really what always happens. it's an extreme permanent solution for extreme permanent dysphoria. many people get along just fine without any treatment at all, and many others do fine if they can just use their preferred identity and maybe go through hormone therapy and the sort if they need it.
