There are a couple of instances that are clearly misaligned with my values, but they're very active, so a lot of the communities keep popping up in my feed. I've been blocking the communities, but it would be pretty cool if I could just block the entire instance. I know an instance can defederate from another instance. Is there a way for an individual user to do something similar, short of spinning up an entire instance myself?
You seem to be the one that doesn't like hearing from people who disagree with you if you're looking for ways to ingore entire instances based on your hurt feelings.
Hexbears are just trolls. They generally aren't coming into threads to have real discussions (and when they make attempts at it they often seem confused about their own stated ideology) - the unstated goal is to be disruptive to deny "shit libs" a platform.