I want to be as gentle as possible and just kinda point some things out that I'm reading as a stranger. I don't think anyone is blaming you or trying to shame you about the ass beatings. You've put up with a lot and not calling the cops kept it from escalating. It sounds like you've got solid boundaries in place now so hopefully you can look back on all of it a little more relaxed and from an outside perspective like I'm forced to have.

You gotta understand, we're all a little crazy dealing with life. Mental health ranges from having a stretch, to full on institutionalized psychiatric care. A person can sit down with a therapist for years and never open up to get a proper diagnosis. Behavior disorders can have no neurological symptoms, chemical imbalances can go for decades without being discovered. Sometimes the systems just aren't able to provide the right support because there's no flashing red sign to point too.

He seems like a functional adult from what you've described. Probably have a lot of "ok" moments with him where it just makes you want to smack him upside the head when he starts doing the fuckery shit. There are so many other things to do in life besides shoving hamburgers in your pocket and giving your parents the worse algorithms after searching "help son stuck on bed post" online. I enjoy gaming and tinkering while also coming on here. I could be carving a special tree in my back woods for some play-time, but I never learned and/or didn't have the wiring to enjoy sexual pain as a release and gratification (not kink shaming, just not built that way).

We all have stupid shit we could be getting into, thoughts that come into our minds or dark paths we decide not to go down. It's that impulse control that keeps you floating above water. You could argue that he "physically has the ability to use that control", but regardless of the wiring, it's not being used. His actions have a negative effect on the people around him and are harmful, even if it's behavioral and a "daddy didn't love me enough" kinda excuse, you will still need support and proper guidance to address the issues (sometimes shit's just too tough for people to handle on their own, a lot of us suffer in silence and some don't even want to know anything's wrong).

Support can have it's limits. But at that point you seek other support mechanisms, we don't really have a functional mental health system that can lead you to the next steps properly. I'm sure there was more recommendations to address his behavior but it probably became circular with no real progression.

A lot of "Ryan's" are in jail because they stole from the wrong person or didn't have a community like you guys were to him. There's a lot of Ryan's running around everyday that you pass by but they keep their shit together for those fleeting moments to seem normal. idk what else to say really, I hope you don't have any more run-ins with the guy. Just sounds like a horrible experience and that's gotta be stressful as a family. I feel sympathy for him though, hopefully he finds what he needs for a more peaceful rest of his life where he's able to make the decisions that benefit him and those he loves around him in the future.