> I'm seeing "I thought I had ADHD and ChatGPT agrees!" at an alarming rate in a couple communities I'm in with a lot of younger people

This may be caused by ChatGPT response patterns but doesn't necessarily mean there is an increase of false (self-)diagnoses. The question is: What is alarming about the increasing rate of diagnoses?

There has been an increase of positive diagnoses over the last decades that have been partially attributed to adult diagnoses that weren't common until (after) the 1990s and the fact that non-male patients often remained undiagnosed because of a stereotypical view on ADHD.

If the diagnosis helps, then it's a good thing! If it turns out that 10% of the population are ADHDers then let's see how we can change our environment that reflects that fact. In many cases, meds aren't needed as much when public spaces provide the necessary facilities to retreat for a few minutes, wear headphones, chew gum or fidget.

The story of your friend sounds very bad and I share your point here, completely. But concerning ADHD, I still don't see what's bad about the current wave of self-diagnoses. If people buy meds illegally, use ChatGPT as a therapist, etc. THAT is a problem. But not identifying with ADHD itself (same for Autism, Depression, Anxiety and so on).

ADHD may or may even be a reinforcing factor for a LLM user to be convinced by the novelty of the tool - but that would have to be empirically evaluated. If it were so, then this could even contribute to a better rate of diagnoses without ChatGPT capabilities in this field contributing much to the effect. Many ADHDers suffer from failing at certain aspects of daily life over and over and advice that helps others only makes them feel worse because it doesn't work for them (e.g. building habits or rewarding oneself for reaching a milestone can be much more difficult for ADHDers than non-ADHDers). I'm just guessing here and this doesn't count for all ADHDers, but: Whenever a new and possibly fun tool comes along that feels like an improvement, there can be a spark of enthusiasm that may lead to an increased trust. This usually decreases after a while and I guess giving LLMs a bit more time of being around, the popularity in this field may also decrease.