@molly0xfff If they offered direct transfer, you could keep your money in the HYSA until the due date of your Amex balance, then pay the balance. Where's the profit in that for Amex? They make money when you pay late.
@newstik you can do that with their standard savings, why not the HYSA?
@molly0xfff I dunno. Probably because the HYSA pays higher interest, so they'd lose more money?