This isn't the first proof of work "captcha" system, there's several already out there.https://mcaptcha.org/https://git.sequentialread.com/forest/pow-captchahttps://gitgud.io/fatchan/haproxy-protection/
Stallman Was Right @lemmy.ml RobotToaster @infosec.pub 3y ago Facebook turns over mother and daughter’s chat history to police resulting in abortion charges www.theverge.com /2022/8/10/23299502/facebook-chat-messenger-history-nebraska-teen-abortion-case
This isn't the first proof of work "captcha" system, there's several already out there.