Thanks for the interesting idea! Not having to worry about free relay is a nice benefit.
Took me a while to get the claim, probably should have started with this. Many implementations do no mempool monitoring at all, so I was confused what this was accomplishing. What the claim is is that with proper expiry, replacement cycling is a just a more time insensitive grief vector, which makes the mempool scanning some may do as a partial mitigation, like LND , completely unnecessary. Wtxid grinding and rebroacasting also become unnecessary at least in theory (I think there are valid reasons to do it anyway)