Thanks for the tag! And yes, it's both. Flowers and Mekka both talk about "HOA racism", the more casual stuff including micro-aggressions ... there are bunch of examples in my post.
In a lot of ways the hard-core harassment from bad instances is easier to deal with -- instance-level blocking has its downsides but is great for this use case. But there are other instances that have a pattern of racist behavior that aren't widely blocked.