I know about this abuse since I used to work in a State Psychiatric Institution back in the 80's as a Speech Pathologiest. I was not working there when the institutions were closed but heard the patients were released to the streets. And that was just as bad for many of the patients I saw who were there for so long. (One I worked with and her sister were both there for schizophrenia most likely bc as young children they were used to entertain their father's friends. ( He was a distinctive lawyer in the state). I can't imagine the one I worked with being able to mange living on the streets at all. She would have not lasted a week.

You are right about the abuse. I saw it and had to counter it when I was on a wing and a patient was tied to four posts of the bed naked for acting up in a shower. I was shocked anyone would be treated that way. The least the staff could have done was cover her with a blanket! I had to find a blanket myself and cover her. The patient thanked me. I reported staff on ward to upper management but probably to no avail,

Unfortunately, abuse is rampant in institutions of all kinds (nursing homes and even day care centers come to mind) when families are not involved. I have also worked in these, but the abuse is more likely from one individual than the whole.
I have also worked in good nursing homes where the patients are treated like family. Sometimes a good nursing home may have one wing that is bad bc the head nurse is not very good.

There is NO good solution when people are evil and do not have any morals.