They already bypass the mempool with services like slipstream and others. Why make it easier? Idk where you got the 4X higher fee from. It doesn’t follow that it would be more expensive to convince a miner to include a txn off band.

Why make a change that would allow bad actors to litter the blockchain with CSAM in such a fashion that would give governments a legitimate reason to outlaw running a node?

Make it make sense