The CAPTCHA Never Tested Humanity, Only the Price of Machines

For two decades, the CAPTCHA asked a simple question: are you human? What it enforced was a price. Distorted letters and traffic-light squares never measured humanity. They measured whether attacking was costlier than the work. A 2025 USENIX paper describes Halligan, a solver built on a general vision-language model, which cracked 60.7% of 2,600 challenges across 26 types, and 70.6% of live challenges over 30 days. The authors concede their prototype is slower and dearer than human farms, which shows where the real wall sits. Every visual puzzle was a bet that machines would stay expensive. That bet has lost, and the bill has landed on people squinting at crosswalks, who were never the threat.