Currency isn't a homebrew computer or backyard car project; it is either centralised or not; there is no in between.
Blockchain with central authority is the worst of both worlds.
And if it is centralised, what is the point of blockchain? Just run it out a Postgres database.
Not really. At a traditional bank I have to trust n people with varying degrees of access. Et ceteris paribus, any reduction in n is an improvement, even if n is not zero.
Of course n can be smaller and the specific people less trustworthy, but that's quite a different thing.
Very much this, it’s all the technical rigour, code debt, and none of controls/reversibility.
At least when I report fraud to credit card or my bank, they can stop or undo/chargeback a transaction.