I think the costs involved in financial services are often more nuanced than given credit for. The nature of the services provided aren't simply a communication

I think the costs involved in financial services are often more nuanced than given credit for. The nature of the services provided aren't simply a communications protocol, not that banks treat communication protocols as rounding to free. (Chase can call up Bank of America at any time and frequently will do so, up and down the banks' operations, every banking day of the year. Those calls aren't free, even if the direct cost of the call time rounds to zero. There is a substantial human and technological overhead to permit the calls to go through and be useful to both sides.) With ATMs as a concrete example, you don't just need a rest API connecting the ATM to the issuing bank. The transaction also involves multiple risk transfers, mandated-by-regulation accountability if something goes wrong (including SLAs for resolution with effectively mechanical penalties for breach, in many cases), 24/7 staffed customer support that answers questions like "I am in New Orleans and a machine just ate my card heeeeeeeeelp!", etc. Now we, as a society, could decide "You know I like a US- or Japan-style penetration of ATMs in society placed by a combination of banks and independent entrepreneurs, but I hate that they actually cost money to end consumers. We should shift the cost of them to... OK I care about the specific payer far less, actually. Let's write a law to do that." Some societies have chosen that.