from what i understand, australia is one of the furthest along this road:

• instant, free bank to bank transfer for amounts under… i think its $2000 (and there’s a bunch of safeguards)
• you can register phone numbers, email addresses, ABNs (australian business number: every business has one), etc and just pay directly to that - again, this is directly in your banks app
• pretty much everywhere accepts credit card tap including phones, watches, etc (though some places add a % fee, that’s for all credit transactions not specifically tap)
• newer banks have a 100% online <5min process for opening accounts, even for new customers: ID check is done in your phone by uploading a photo of your drivers license (i actually opened a bank account with a new bank while i was in the US sitting in a restaurant, transferred money, added apple pay, and then tapped to pay all over dinner)

most people i know never carry cash, refuse to go anywhere that’s cash only unless it’s the only option, etc

granted i’m in a younger, technically-competent group, however my experience is that whilst physical currency isn’t dead, tbh i get annoyed at people holding me up fumbling around with it trying to pay: it’s just so rare, it’s almost a novelty at this point