I don't care if this outs me - but it's a subject that I've experienced and I know how it hurts.
I have a son who is older than yours, OP, went to uni overseas, had a career planned and then Covid hit. Took away all his prospects overnight. Depression and drugs set in. I found enough in my house to either kill or go to prison.
Now - this is a young man with 10 GCSEs, 4 A Levels, a BSC and an MA. We gave him harsh love. No one will love him as much as his family. These friends don't give a shit. They'll desert him and he'll be in a shop doorway every night, no clean clothes, eating rubbish donated and will not know of family occasions, births, funerals, etc. Make that choice. Always here for him and will always help, but he's got to make that decision himself. In a word, we frightened him witless. He would lose everything. He tried to kill himself on the railway line, but there was a signal failure that night, and no trains....
It's been two years of difficulty, and he's only now beginning to communicate properly. He has a managerial job - not one he wants, but one he has accepted as a new career. And I hope to God all works out well.
As I do with you and your son, I really do.