I've wondered if it isn't intentionally impossible to solve, because "the algorithm" decided that you're a bot or malicious and they want to spin your cycles endlessly. The affect on me know is I won't even try anymore, I'll just take a different route. That may even reinforcement teach the system that I was a bot that couldn't solve it

I think it's more malicious than that. They know I use privacy tools and can't be tracked -> they can't make money on me -> bully me into not using their service.

It may also be part of their anticompetitive war on other browsers. I get captchas constantly in a new default Firefox profile, but not in a new default chrome profile. Spoofing user agent to recent chrome agent in Firefox makes the captchas happen far less often for me.

I sometimes get multiple captchas in a row that I fill correctly but they keep on showing more..I then just do the audio one which works.

This is probably the common thread among all the people reporting this. As an alternate date point, I haven't experienced the captcha from using advanced search queries.