You can focus design towards a strong sovereign-monetary decentralized trustless censorship-resistant digital currency ; Or towards a fast less-decentralized digital currency + non-trustless censorship-vulnerable payments network.
Choose.
Can't prioritize both - as the ol' bearded coder explains, there are 'engineering trade-offs' that need to be made when working with reality.
Nobody wants to replace debt. There will always be people willing to sell their futures into slavery. The credit cards are in no danger.