I like a lot of what’s being discussed here. One thing to consider is a similar problem I am facing is people trying to hack into a login page. We see thousan

I like a lot of what’s being discussed here. One thing to consider is a similar problem I am facing is people trying to hack into a login page. We see thousands of requests per minute from different IPs… many from VPS, some from obviously hacked TVs/devices. We could implement an exponential back off on abusive IPs but detection requires observation of action that action could result in a compromised account… so another idea is we simply block large ranges of know bad IPs from blacklists… I think this is similar to the email sending issue… it’s not fair and I think a solution could be some kind of “block chain” - make it expensive to login… make it expensive to send an email… but I’m not sure and for email it’s way harder because you need agreement from the oligopoly of email providers… not sure what the solution is