but some other secure facility that maximizes the ability of these people to make whatever contribution to society they may be able to make to society.

Yeah, I touched on that with my last sentence:

It may be called something else in the future (like a long-term involuntary mental health facility,) but it’s still serving the same basic function while wearing a more friendly mask.

There are two problems with that. The first is that “maximizing contribution to society” can easily be interpreted as “being forced to stamp license plates for 16 hours a day.” We already know this is a possible interpretation, because that’s how our system already interprets it. Either way they’re locked up against their will, and are being forced to perform labor to someone else’s benefit. The very nature of their confinement means that any contribution they make will be for someone else and not themselves. And the simple word for that is “slavery”. The second problem is that it’s still prison. We haven’t actually solved the prison problem at all in this scenario; We’ve simply given it a mask so we can say prisons have been abolished. Like if we don’t call them prisons, we can say we don’t have any prisoners.