At what point do we consider filters an argument in bad faith?

Running knots is a free choice. Am I right with the following? If Miner (pools) do not run knots, there is change with spam in OP return. However there will be a problem or delay by propagating blocks. Possible causing nrw problems. So in summary knots node runners only signal not supporting core v30 and thus do not want spam on their disc. I do not take position hete, just want to understand the subject.