The whole SEPA area has instant SEPA payments. You can stick that into QRs or whatever. Some merchants take payments by SEPA, instant or not, but we need something else if we want to replace both online and in-person card payments throughout the whole EU, and at this point I doubt the Wero will be the replacement.
Not everyone is in eurozone, there are countries with instant QR payments that are not SEPA. It is nowdays quite common to get a QR with your invoice, online or in person, it might not be just SEPA. But for now cards are still more accepted, and work even if I leave my phone at home or it rans out of battery. Not sure how Wero or QR going to solve that, SEPA or not, but still useful for a lot of cases, online payments etc, even if it does not solve every edge case.
Every EU country even outside of Eurozone is in SEPA. But SEPA payments can have their own issues - I believe they were not free in all countries some time ago, not sure what the status is currently.
There might be other instant QR payment systems out there though - I digress but on our recent visit to China we had to use Alipay as the cards are not accepted at most places and of course it works through scanning QRs, either you scan the vendor's code or they scan yours, and then you enter or confirm the amount and that's it. But the issue I have with these systems is the same as yours - we are fully dependent on our phones with no backup.