The problem is that crypto is designed to evade regulation. You can put lipstick on a pig and regulate the centralized intermediaries (which, remember, crypto aimed to disintermediate): exchanges, custodians, ETF providers, ...

The dilemma is that you can either escape those regulations by going to unhosted wallets (self-custody) and transacting on the blockchain, or you keep everything (by regulation) entirely within the regulated intermediaries, but then there's no need to waste 1% of world electricity on some slow "decentralized" database.