Honestly, if these instances don’t get their act together, I’d vote on my instance to defederate from it.
I’m usually not one calling for defederating, it seems like a liability, though.
The beauty of the fediverse and the power of ownership is being able to take decisions like these.
My thought were the same way about not wanting to call for defederation, but after thinking about it and owning an instance of my own now, I realize that that is the whole point. Instance owners can block entire instances from federating with them. If every instance blocks an instance that is a bad actor then they literally can’t federate with anyone and that solves the issue.