“It works extremely well” doesn’t establish “its prices and restrictions are justified”. much better, less parasitic systems are possible, look at brazil and PIX. "These networks would be usurped if someone could actually come up with a better system" the problem is the network effects with payments is so strong that this is wrong. to explain it simply, Network effects and customer lock-in mean the best system doesn’t automatically win.

I 100% agree that their business is operated extremely well and delivers lots of value.

I am just saying that in my opinion, society would be even better off if this industry wasn't controlled by a cartel and i pointed 2 examples of how.

One difference between this and turbines, is that payment networks are sitting at the heart of the economy of countless countries. Turbines have a very different risk profile, much more modest and localized.

Russia was for example cut off from high-tech maintenance contracts but has been able to deal with it by manufacturing their own replacement part + there are maintenance cycles and spare parts so any disruption in service is not immediate unlike payments.