I enjoy Discord servers but for some reason I can't put my finger on getting involved in a Discord server feels like a lot more effort than getting involved in a forum. Maybe a part of it is that there's a little less anonymity unless you're willing to make different Discord accounts.

Discord I also think is bad as a platform for sharing fic. You could post fic directly to Discord but that's ephermal so a lot of people end up sharing links to gdocs or screencaps and that's not really accessible.

I do think Discord ends up as a good place to find community if you're willing to put yourself out there and really get involved.