It will be much more productive if individual nodes can opt-into UTXO freezing and deleting rather than a consensus change that needs approval. As a node runner, which all NPC Bitcoiners need to become, I want the freedom to modify my node as I and people like me see fit. I do not want an artificially large chainstate with 40% dust outputs clogging up my RAM and sitting idle on my disk. As far as my UTXOs, I have them saved and can send them whenever I see fit. I don't have any dust and I certainly don't have any spam. The CAT as a soft fork is likely to get FUDed out of existence and I would prefer a more self sovereign solution to the spam problem should this fall flat.