Perhaps the game changer if I understand this piece right is self custody. There is no longer a need to store funds in a bank. Though people still will, even on a Bitcoin standard, and so yes, that flaw of banking still needs work done.
Discussion
Imagine a world which has fully embraced Bitcoin.
Everyone in the world uses Bitcoins as their "money". Some people self-custody, some people have their Bitcoins in a custodial arrangement (eg Wallet of Satoshi).
International commodity markets price goods in bitcoins. Crude oil is a few thousand satoshis per barrel.
Stock markets are priced in bitcoins. Contracts are written in bitcoins. Mortgage loans are made in bitcoins.
All of this contractual activity and remote exchange requires not just a trustworthy money, but also reliable security, dispute resolution, and enforcement. But if that reliable courtly authority is available - why would we use bitcoins rather than gold? Or any other commodity? Say, palladium.
Why do you assume I could successfully enforce a contractual claim on oil, or stock equity, or even Bitcoin itself, but I could not enforce a contractual claim on metal disks?
This is my point.
Bitcoins are supposedly a trustless currency, but to do anything worthwhile - even in the presence of trustless currency - still requires trust.