Lately, a lot of Recaptcha challenges are things like - identify the trucks, the cars, the shops, etc. I really hate these challenges knowing what Google will (at least in part) do with the data.
IIRC, original Recaptcha was about OCR of books that weren't readable. I'm not sure why anyone uses it right now. Like you said, it's obvious where it's going. Not to mention that it's increasingly annoying for users.
And completely accessible. RECAPTCHA is basically impossible to use if you need a screen reader or have any sort of visual impairment. Hell, I’ve have problems as a EU resident due to differences between street signs between here and the US.