I think that the (dead, gay) Something Awful forums model is a decent solution to content moderation and monetization. An account is 10 dollars (lifetime). If you get banned, you have to pay 10 dollars again. Permabanned = can't come back. Premium? (dms, search, custom avatar) 10 dollars. Change your avatar? 5 dollars. Change someone else's avatar? 10 dollars. Ad free? 10 dollars. Access to archives (posts over a cer…
You're missing the most important detail of why that worked. Forcing payment solves issues surrounding identity. Permabans on other platforms don't work when you can make a new email and sign up again. Sure, there's a cost to bans ($10) but it's minimal, but evading a permaban means finding a new means of payment not linked to your identity which is a lot harder. Not impossible, but enough that it stops most bad acto…
Also, on the forums, you can look at anyone's rap sheet and see exactly the post that they got banned (or probated or permabanned) for. Let's you know what sort of person you are dealing with.