If Discord ever did need to become ad-supported (not that I ever want it to!!), it could actually strike an interesting middle ground.
Facebook's problem is not that it controls which ads a person sees based on their content and communities, but rather quite the reverse: it controls what content and communities a person sees in order to increase their engagement with ads!
Discord, if it were to maintain a strong commitment to a "one way flow" of information towards ad targeting (without leaking that information to advertisers, of course, which is easier said than done) and not towards content promotion, could find a sweet spot where it is not possible for them to ever enter the business of being incentivized to promote misinformation - except insofar as paid ads are the misinformation, which is still a problem but at least a more traceable and manageable one. People would still discover and choose their communities organically, and the mods and participants of communities would control their outbound edges of the discovery graph.
Of course, not being able to optimize the bulk of a user experience for engagement is somewhat anathema to both the data scientist and product management instincts in me... but I honestly would much rather work on any B2B recommender system, or even an ad system like the aforementioned one, than blindly write code that has now been proven to do harm.