thanks for sharing that. What do you think would make a better solution?
there are many issues with it, but the unsolvable one is that it can't be scoped enough to not be trivially abuseable, and the more it's scoping capabilities are increased the heavier the burden on relays and clients
also, here are fiatjaf's notes about it too https://fiatjaf.com/4c79fd7b.html
Discussion
NIP-46 allows for the application of any policy in an HSM-style (infinite-level expressiveness of signing policies) without any demand on clients or relays.