This reminds me of a thread on the DX forum many years ago (I don’t participate much any more) where people were trying to describe hospitalization to uninitiated person who was recommended she might benefit, but was trepidatious to go because of misinformation in media. Most said it was similar to summer camp, and I can’t help but be reminded of Allan Sherman’s song, A Letter From Camp (Hello Muddah, Hello Faddah) in your son’s case.
It’s been a long time for me, but when I was hospitalized your day was structured into communal group events like meals and exercise and such, and ‘activities’ which were smaller groups focused on interests or therapeutic activities and some free time. A day or two after you get acclimated, staff gives you a schedule of events to go to. I found an alternate schedule printout of mine as I was leaving which was better tailored to my interests (it had numerous music therapy sessions). I’d been working from a generic schedule I received after admission, and was unaware it was updated. No one seemed to care, and I was sometimes solicited by friends to attend their sessions. In a sense it was a bit like work or hobby conferences with breakout sessions and such, but with more guidance and structure.
The staff would opine to some patients that they’d miss hospital after they left, because they wouldn’t have activities set up for them and friends to hang out with etc. I think this is a void the clubhouse system tries to fill, but I fear these organizations are suffering under COVID.