Even if the success rate of detecting robots stays the same, I would say this is still a win because the majority of humans won't have to mess with it any longer.
Even better: those with various disabilities won't have to mess with it. My parents' only disability that I know of is near-complete computer illiteracy and I can tell you from experience that every time they're presented with a normal CAPTCHA it's like somebody just handed them a Rubik's Cube and told them to solve it before they can create a profile. In every case I know of, they just turn the computer off and walk away. Now, these are what I would call normal humans (don't tell them I ever said that) so I can only imagine how aggravated those with visual and/or auditory problems get when presented with a crazy CAPTCHA. And when your revenue comes from getting people to submit these, I can see it still being a boon to the website, even if all they did was lower the barrier of entry for humans.
Even better: those with various disabilities won't have to mess with it. My parents' only disability that I know of is near-complete computer illiteracy and I can tell you from experience that every time they're presented with a normal CAPTCHA it's like somebody just handed them a Rubik's Cube and told them to solve it before they can create a profile. In every case I know of, they just turn the computer off and walk away. Now, these are what I would call normal humans (don't tell them I ever said that) so I can only imagine how aggravated those with visual and/or auditory problems get when presented with a crazy CAPTCHA. And when your revenue comes from getting people to submit these, I can see it still being a boon to the website, even if all they did was lower the barrier of entry for humans.