Some people are lost to AI fascination quickly because they're curious and maybe a little lonely, or at least isolated.
Suddenly, they have a oracle that can endlessly tickle their curiosity (accurately or not) and follow them as deep into discussion as they can imagine, without ever growing tired or annoyed.
Unfortunately, in many ways, there's a lot of overlap between those people and those that had once made great community members online. They had the curiosity to have already dug deep into topics so as to become knowledgeable about them and discovered interest communities online as a place where they could invest themselves socially and feel less alone. Online communities were good for them and they were good for the online communities.
The story you relate here is not singular, and it's sad one to see, as it likely means these people are going to eventually find that they've lost the esteem and social credit they'd spent years earning and are now as alone online as they ever were before.