Whilst a valid concern, the workplace is a vastly different environment from the school.
I think that IF you can get a young adult into a workplace, you've probably won the battle as they'll find it a much more supportive, mature and rewarding existence compared to a school (in general terms, I know some workplaces can also be toxic). Just being around adults is often enough!
Obviously, someone with stress, anxiety, low self esteem, etc., may not be easy to get into a workplace though!!
The thing is most schools seem toxic these days. All the nonsensical rules, endemic bullying, noise, disruption, etc., being forced to sit in lessons they can't understand, etc etc.
I hated school due to daily severe bullying and ended up truanting and leaving without any qualifications at all. I was withdrawn, suffered low self esteem, had an eating disorder, no friends to speak of, just stayed in all day, literally doing nothing. With help/support from parents (basically pushing me, dictating application letters, etc), I went to a few interviews, and massively gained confidence from each. Out of 5 applications, I got 4 interviews and 2 job offers as "office junior" which was all I could expect with no qualifications. I was a nervous wreck in the days before my first day. But I loved it. I was in an office with two "older" ladies who really took me under their wing - I think they could see I was "tainted" by my awful teen years. I couldn't believe how nice everyone was, I was constantly expecting to be told off, bullied, etc., but it simply never happened. I literally grew in stature and confidence every single day. After such a good experience, I started going to clubs & societies, started a sport, did O and A levels at college, etc., and constantly surprised at how different it was to be in a mature/adult environment rather than school!!