I agree completely. The worse this gets, however, the less reCAPTCHA makes sense to me. The main reason to use it was the fact that it worked invisibly for user

I agree completely. The worse this gets, however, the less reCAPTCHA makes sense to me. The main reason to use it was the fact that it worked invisibly for users it deemed as not being a bot. Based on the responses here (as well as my personal experience) this seems to work less and less now - maybe partially because Google wants more users to train it's algorithms. Therefore there is not much to distinguish reCAPTCHA from some other CAPTCHA system, including simple ones you could make yourself. The image recognition stuff requires more work but, arguably, we are even worse at basic NLP tasks, which are even easier to make CAPTCHAs for. All you need is some private dataset, which you can create manually fairly quickly, and a corresponding task. For example: Select which of the following are fruits: 1. banana 2. firetruck 3. baseball 4. apple On top of that, if there were independent implementations of CAPTCHA systems the exact mechanics of interacting with the CAPTCHA would be sufficiently different that the very act of submitting responses would, itself, be a bot test.