I have been paying too much attention .. Hours of podcasts and discussions here ...

I will probably just run core 29 just to humble those blue haired core devs.

But that's it. Apart from this signaling it does not matter what mempool policy I or anybody else (except mining pools, which are like 10 entities) runs on their node.

100kB OP_RETURN is consensus.

And it does not even make sense to use it for spam since ordinals use witness data which is cheaper and has no limit (whole block can be 1 jpeg)