My 2 cents

I don't think it is strange, I think a payment system is a natural monopoly of sorts. The customer experience is generally improved if we all agree on one system. I don't think you'd want a dozen providers connecting your electricity with wires all over the road, and I don't think we want dozens of payment systems with patchwork compatibility.

2-3 systems feels about right, for redundancy if there are technical issues on one, but limiting how many cards we use.

It's a remarkable achievement of our time that we can carry a single piece of plastic almost anywhere in the world and be connected to a vast payment system in any currency, and it's incredibly reliable.

But given it's a natural monopoly, it definitely needs regulation of pricing, and it also needs viable plans if shit hits the fan and international cooperation isn't on the menu anymore.