Just so everyone is aware, he's not advocating for fungible tokens. He's opposed to fungible tokens.

He's trying to propose a fungible token standard that's better than BRC-20. BRC-20 transactions leave little dust UTXOs littering the chain, and it's a major reason for the UTXO bloat since Ordinals came out. He's merely trying to propose a system that he hopes is better and will overtake it, for the sake of the UTXO set.