Are there any 5.5 physical sourcebooks? Were they ever planned at all?
I haven’t been following One D&D news, but I got the impression they were focusing on a subscription-only model, so I’ve been planning to stick with my 5e books or switch to an ORC-licensed system.
A web forum is far better in most cases. If you can’t manage to run your own, there are plenty of lemmy servers that will do it for you. Even an email list (with searchable archives) would be better than Discord.
If you have collaborative documents that outgrow the forum format, use a wiki.
If real-time chat is needed, irc or matrix.
A project hosting its community on Discord is a project that won’t get my contributions.