Suspending payments at banks usually are used to avoid bank runs. I believe the parent was trying to point out that crypto is learning why banks are the way they are now.
Indeed. Defi/Crypto can't solve all of the problems that banks are faced with.
That's not how most banks work, you may have been at one that had the person with authority but transfers over certain amounts ($1M around here) require multiple reviews and certain people. You can do it in a day (and regularly do for wires) but it requires additional steps and authorization. Banks also don't necessarily have all of the cash you'd need on hand.
Not in the EU. Banks tend to not allow you to do that