The filters work perfectly at their main job: keeping spam out of your mempool When widely adopted they also delay the propagation of spam-filled blocks, which provides a nice monetary incentive for miners to ignore spam: ignoring spam = fewer blocks orphaned = higher income

That's not an argument. During the height of the spam craze people saw that giant spam txns with huge fees were not being distributed to pool participants as they should have been. Ocean showed that even very early on participants were earning more in spite of filters. Datum allows miners to process whatever txns they want. So it dramatically decentralizes mining & takes power away from pool operators. And it does appear to be the case that legacy pools are corrupt (which really shouldn't be a surprise since more than half of them are Ant-main anyway).