I wanted a more pseudo-anonymous form of this, which is why the message board I built is invite only (still pretty new). I think if you prune bad inviters, you can build a really high quality user base that is still mostly anonymous (depending on their username).

Still very early stages, https://filigree.app if you'd like to check it out. Invite code kris-75c23bae7837 if you want to register.

Edit: quite a few people registered, so I'm deactivating that invite code.