Yes and no. Traditional CAPTCHAs didn't cause bot farms to advance computer vision
The ultimate challenge is to replicate end-to-end natural human cognition, which is currently an unsolved and hard problem (and also not necessarily the main focus of AI researchers).
Are you sure? And how do you know?
There are a lot of CAPTCHA cracking services. Given the price, they are hardly sustainable even under developing country wage level. I believe they actually solve the easy ones automatically and humans are only involved for the harder ones.