Can't you access Discord in a browser?
Even then I still have my reservations, because Discord in the browser is clearly "the Discord app running in the browser", while most traditional forums are actually rendering different pages for every thread and forum. That has big implications on things like indexability (by search engines), archiving and so on. We will see.
Overall I think a return to forums is good, and if that return takes a detour over Discord, so be it.