UK Open Banking is a counter example to this argument. It’s been a huge success. Transfers between accounts are seamless, and I never need to authorize Plaid to maintain a permanent session in a headless Chromium instance reading my bank account. The APIs are well-defined, universally supported, and include authorization scopes for viewing balance, authorizing transfers, etc.

That said, I don’t do many p2p payments in the UK (mostly because I’m an adult now, not splitting every bill like I was in college). And I wouldn’t like to add every one of my friends to my banking transfer history. The UK is missing something like Venmo with wide adoption. I assume the kids these days mostly use features like Apple Cash or Monzo transfers.