I could never figure out how that would work, or why. I mean, was Google actually doing this? That is hard to believe. But, who else would a have motivation to do that? I still have no idea what was going on there.
edit: I haven't dealt with ads forever, what I meant is the Google ads that appear in google search.
I bid on "seating plan" for my seating planner software in Adwords and lots of people searching for "747 seating plan" and similar clicked on my ads, despite the ads clearly being nothing to do with that. (I fixed with with setting "747", "a320" etc as negative keywords).
I don't think this is sufficient to account for the terrible engagement from ChatGPT ads though, unless the targetting is just garbage.
I have also audited other people's Adwords account. The horror.