A friend has been interned in a psychiatric hospital for a month and counting for some sort of psychosis, regardless of the pre existing conditions chatgpt 100% definitely played a role in it, we've seen the chats. A lot of people don't need much to go over the edge, a bit of drugs, bad friends, &c. but an LLM alone can easily do it too
If they have the predisposition for it, a month or two of bad sleep and a particularly compelling idea may be all it takes to send a person who has previously seemed totally sane into an incredibly dangerous mental and physical state, something that will take weeks to recover from. And that can happen even without sycophantic LLMs, but they sure make this outcome more likely.