a thing that makes these methods a dead end for consumer payments is cash finality and the fact that fees are paid by the buyer. if you look at how consumers pay today (credit cards, cashback, BNPL) it's clear that they don't value privacy much and being debt-based has advantages for them. UX doesn't matter if consumers don't have incentives to switch. banks already have earned people's trust and there is usually a physical space you can go to complain, mints on the other hand..