If mempools aren’t there to express personal preference then why are they not consensus rules?

You are projecting your personal preference of removing the limits on OP_RETURN with no way for users to opt out (aside from not updating or running knots) and have the audacity to say that the people who want to keep bitcoin the same are using the mempool to express their personal opinion is some backwards ass logic.

The reason why libre relay isn’t enough for people like yourself are that not enough node runners are opting to run this spam blasting node on their own and getting spam txs in blocks is still difficult. Thats why spammers are pushing for bitcoin core to make this policy change and their hope is that 1/2 of the node runners who are running the most current version blindly update to the latest version and propagate spam.