The mean thing about psychosis is that you don’t realize it. For him it was reality. Mental health education is key. If you notice someone in their early or mid twenties become reclusive and feel paranoid, notice a professional. As his friends should have done in college.
Btw, under psychosis people are unfit to plead, if that’s the right term. So it’s difficult to call him responsible.
I use blokada. I have no idea how it works or if is safe, but I haven’t seen an ad even in apps since I installed it