Erik
Yeah, now that I have the information about the person with 1,000 accounts in a day, I see more logic in your decision to implement this restriction. However, I believe you could have also banned this person from creating more accounts and then announced these restrictions over time. By doing it abruptly, too many people have been harmed by this implementation.
A ban won't stop the behaviour, it will only make them do it again more slowly or with other IPs. When solving it, you have to think also how you would just do it again but differently, so it has to be stopped using more advanced detection, which is what we rolled out.
Anyway, for now, it's reverted. Back to the drawing board.