I need to use this thread to mention the Polish payment system Blik. It is one of the most convenient payment systems out there - you generate an ephemeral 6-digit code in your banking app, copy it to the vendor, confirm, done. Works P2P with phone numbers, too.
Interestingly, it would be the perfect system for payments using AI agents - the agent tries to pay, asks user to provide 6-digit code, submits payment request. User confirms via banking app. Done.
There's an interesting angle to BLIK vs Wero. While I believe QR codes are more convenient it is actually possible to give BLIK over the phone. Which means that youngsters (or fraudsters ;)) have access to their guardians' money over the phone line.
There is also a Blik feature to pay in one click - merchant remembers your payment and allows making subsequent payment without code, just by confirming transaction via banking app.