> “Breakup” seems a bit exaggerated considering the % of payment volume which might switch to the new system.

Brazil introduced Pix in 2019, it's now the most used payment method for all transactions nationwide, ahead of both cards & cash.

India introduced UPI in 2016, it now handles >80% of digital payments there, and handles more transactions a day than Visa does worldwide.

It's totally plausible to me that a similar replacement could overtake cards completely within a decade. The lack of cross-border support means "Pay with Bizum" is a niche feature that's only useful in Spain, but if "Pay with Wero" becomes an instant & ~free payment method that works for hundreds of millions of users then it's a very different ballgame.