First, SEPA instant payments already exist and are really instant up to a certain amount, and I am guessing that Wero builds on top of that a sort of identity layer, to sidestep the whole IBAN thing. But it is likely more than a SEPA alias, since it was supposedly hard to set-up.
Second, VISA and Mastercard are worldwide payment networks (or rather, they each operate payment networks with various names?). But I am failing to grasp what's hard to reproduce here too. I heard that in Europe there were only a few national alternatives, like Carte Bancaire or Girocard, but why? Is it just because banks can't agree on the design of an alternate network? But all the fees associated with using VISA or Mastercard should be a big enough incentive to push something else. (basically what's a payment network?)
And lastly, why are all the new (free) digital banks (néobanques as we call them here) relying on either Mastercard or VISA and never on Carte Bancaire for example, while it generally offers lower processing fees (and that they can be cobranded).
I think I am missing a lot of context, and I asked LLMs a while ago about these but themselves don't really explain what is the infrastructure needed to operate such a network.