I have been wondering why Usenet and IRC haven't experienced a resurgence. Discord will be the next casualty of corporate greed. It's really a fallacy that these communities are moving to yet another corporate-controlled entity.
But yeah, the fall of Discord is coming. The enshitification process has begun. Their forcing users to use unique usernames still baffles me.
There were in the past - Slack basically bootstrapped itself off the back of techies, with the IRC transport making Slack seem like a prettier IRC... only to shut down the IRC transport once they've entrenched themselves on the market.
Usenet requires special software and often subscriptions, whereas Reddit doesn't.