Question: are US banking really this dysfunctional? Where I'm from, a bank consortium already provided unified login services (while banks still have their own websites, as a merchant you only need to integrate the consortium-provided APIs rather than using Plaid) simplifying things.
Yes. Some banks still run COBOL behind the scenes here.
But the use of COBOL generally doesn’t extend to the consumer facing product, or the APIs that support those consumer facing experiences.
Banks may be backwards, but the use of older languages is not one of the primary reasons.