I disagree. It's not necessarily a false equivalency and depends on whether you think paedophilia is a sexuality or a paraphilia. I think the jury is still out on that one. And I was careful with my words... I wanted a child who recognised paedophilic intent but never wanted to act upon it.
And yes, we all have moral lines we are unwilling to cross and we all have to evaluate the moral landscape.... but I don't think that's what the OP has done. I think they've said 'I support my kid no matter what they want to do because I'm a supportive liberal and I don't believe in boundaries'
And what I was looking for was the answer you've given.... 'not being disowned, but clear boundaries in place and a good solid shove towards celibacy and counselling' - and a recognition (perhaps) that for other people, who might be of the religious persuasion that this is their answer, because what is being suggested by an LGBTQ+ child contravenes their own moral understanding of the world.
That doesn't make their choice right, but it does make their choice easier to fathom - and once you understand someone else's moral code, you can begin to dismantle it. Or, in your case, wholeheartedly approve of it.