If anyone is interested, I have a NodeBB instance at https://constructed.world/. For now email is not required to sign up.
NodeBB seems to be a spiritual successor to phpBB that aims to modernize the traditional forum experience while keeping the community atmosphere. It has many features that phpBB lacks, such as user mentions, a more modern user status indicator system, real-time chat, markdown formatting, and of course, it uses ActivityPub.
I think the more permanent discussion format of forums is a better fit for this hobby, personally.
Hopefully advertising another online conlanging/conworlding community isn’t too crass, but I have no idea how else to let people know it’s available.
OK. NOW email is working properly. Turns out my own email provider is more permissive about random email servers. Gmail won’t even put it in the spam folder. I had to switch to a 3rd party email provider. Before I was using sendmail built into the server. I can confirm Gmail is receiving the verification emails now.