[watwut]

> t's cruel and inhumane to forcibly remove someone's access to something they are personally and emotionally invested in.

Not always. And not in this case. It is not cruel and may be necessary.

> It's cruel and inhumane to force one's own view of a “good life” on someone who obviously disagrees.

Speaking about fallacies, this framing is clearly not what is going on in that situation. In either way, the kid is growing to be entirely unable to live without caregiver of a sort, so yes, it is duty of parents to intervene regardless of kids agreement.