What makes one crime different than the others is the amount of damage done, and the likelihood of the crime being repeated.

The likelihood of it being repeated here is nearly zero... even if he is some kind of a perv, it's clear that he only does these sorts of things in the capacity of his profession, which is now forever denied him.

If the definition of "violated" that we are working under is "raped" or something similarly destructive

I get the impression they're talking about sexual assault, but not rape.

Here you will see the recidivism rates for sexual assault

Yes, I'm aware of those. Which speak greatly to his likely innocence. If he really was guilty, where are all the other accusations?

Sequestering them from the general public is not only a fitting punishment, but a safe one.

But they're not interested in protecting the public.

Instead, they want his confession... as if that protects anyone. Why is that?

Psychologically, we know that humans are a peculiar kind of monkey that loves seeing others confess... regardless of whether they're guilty or not. In the Middle Ages, that's when the torture would (mostly) stop.

That's when it would stop regardless of whether the confession were genuine.

And that's when things are stopping here. He's either tortured in prison, or he can confess to the priest of the therapy group.

So I point out how parole and sentencing have been modified so that they're fundamentally unfair... and you rebut with "he should go away forever, because he needs to be sequestered from society".

It's a peculiar reply. It wants to sound principled, but it rests on a foundation of bullshit so deep that it's just another way of laughing at the man and wishing that things like this continue for him forever.