This makes a lot of sense! if we also enabled TXHASH that would allow people to commit to a spending path that requires multi-step secret reveal. that allows spending under adversarial quantum conditions. In other words.. we don’t technically need signatures at all. This would allow people to vault their coins and spend them safely even if quantum came out tomorrow and we still hadn’t gotten a signature scheme.
see: A quantum resistance script only using op_ctv/op_txhash and no new signatures