I understand what you are saying, but this seems like a very low bar for prior history. Many people are into stuff like that without ever going crazy, which contradicts your assertion they are all disasters waiting to happen. It's also possible for many people to end up believing in some fringe things, but still remain functional.
Of course most people who are a little bit mad are still functional, the point is that gpts are like having a similarly mad friend who encourages you further away from reality when what you need is someone who can get you grounded.
The problem here is we have no baseline statistics.
I'd say my family is a great example of undiagnosed illnesses. They are disasters already happening waiting for any kind of trigger.
These undiagnosed self medicate on drugs and end up in ERs to the surprise of those around them at a disturbing rate. Hence why we need to know the base rate of mental occurrence like this before we call AI caused incidents an epidemic.