I don’t actively discriminate based on a poster’s instance, but there are a half dozen or so instances where there is a very high likelihood that they lean one way or another on different topics. If a post that could be read two ways then their instance can be a pretty reliable indicator that looking at their posting history will confirm which way they lean.

In a couple of cases I just blocked the communities that are the hot button issues for that instance because other communities are worth reading and interacting with.