Health-related communities, particularly those for specific medical conditions. Those are the communities that really become a lifeline for people, help them through diagnoses or just difficult times, and can serve as an excellent resource. I was active on r/diabetes_t1 on Reddit and am trying to get a community started here on Lenny.world (!T1diabetes).

I think we learned in January 6 that allowing these communities to exist online is more than just letting people express a different political worldview.