I tried to find a journalistic-sounding reasonable title for this post, but couldn't. This filter stuff was stupid two years ago when it started, it was stupid earlier this year when all of a sudden everyone thought op-returns were going to be the death of us, and it was stupid back in the summer when CSAM was all anyone could talk about, and it was stupid when they finally got around to proposing a the Reduce Data Temporary Soft Fork.
It's still stupid now. Some idiot called Claire Ostrom, who started posting on X right about the time "Dathon Ohm" stopped posting, has proposed something called "The Cat - Non-monetary UTXO Cleanup."
A soft-fork consensus change and new spending rules intended to remove an existing, snapshot-based set of non-monetary UTXOs (NMUs) created by protocols such as Ordinals and Stamps, by making those UTXOs permanently unspendable and eligible for removal from the UTXO set.
For people who support things like this, why are you even bothering with Bitcoin? "making those UTXOs permanently unspendable" is not Bitcoin. Bitcoin is peer to peer digital cash. It's money you can send to anyone anywhere anytime and no one can stop you. It's not fucking very good at that if some portion of the community gets to decide whether your transaction counts as "non-monetary."
OP_RETURNis a great unspendable output, I hear.utxo setis an implementation choice. Ask Voskuil whylibbitcoindoesn't have it, or askutreexoabout their solution.libbitcoinsimply chooses to store more data than that, whereasutreexointroduces a framework where other nodes can prove that some UTXO exists and is spendable. Everyone still needs to agree that these UTXOs exist and are spendable.utreexois a better solution. If you runlibbitcoinyou don't care about it at all because you basically run full txindex. If you are a miner then don't mine what you don't like. And if you are worried about other miners, buy more ASICs until they are all bankrupt.