I'm a Norwegian who went to a Swedish music festival last summer. I couldn't pay for a lot of things there, since the booths only accepted Swish (the only relevant Swedish mobile payment solution, it's a de facto monopoly). I couldn't sign up and use Swish on my phone, since it only accepts Swedish bank accounts. I couldn't borrow money from my Swedish friends either, since they didn't have cash (and it mostly wasn't…
Canada we have Interac, which is mostly everywhere, but we also have cash, and three or four credit networks (Visa, MasterCard, American Express, and sometimes Discover). There are only really three physical modes of operation, and they all have a time and a place: Tap card 95% of the time, insert and use pin when fraud detection gets a funny feeling, and use cash when all else fails (because sometimes that means you have to call up your creditor's fraud department and let them know you're just on a roadtrip, your card hasn't been stolen).
I don't think requiring a smartphone to accomplish what chip & pin and NFC cards do just fine is an upgrade.
Then these people talk about making state payment processors. What happens when fraud prevention completely stops you from being able trade any money? Do they drive out to fix your problem on the spot? How on earth could they expect that to work out well?