anonymity and privacy seem to come at odds with a social platform’s ability to moderate content and control spam.
If users have sufficient privacy and anonymity, then they can simply use another identity to come back, or use multiple identities.
Are there ways around this? It seems that any method of ensuring that a banned user is kept off the platform would necessitate the platform knowing information about the user and their identity
If they show disruptive behavior that you don’t think is acceptable, ban them. There are very few people who would be motivated enough spend the time to remake an account just to troll and get instantly banned again, and for these people an IP ban should deter them enough.