I would love to see similar public-private consortium systems in rest of the west like Germany, Spain, France and Australia etc. Until then I’ll consider UPI to be superior to those in the west.
I think there is a standard, so as long your bank’s app supports it and more importantly the merchant actually provides a QR code to scan (which is unlikely).
Then again, I don’t see much need for that when I can just NFC pretty much everywhere (of course the merchant still ends up paying up to 1% on every transaction)