Banks already are a decentralized system, just not a very good one. I can send a SEPA transfer from any EU account to any other EU account no matter which banks they are with and there isn't a "SCT processing company" that handles that for me, the banks communicate with each other - the system is decentralized. But that transaction takes up to a day for pretty much no reason, so we use payment cards for most things. Those are centralized. If Visa/Mastercard doesn't want to handle my transaction, I'm screwed. If instead cards simply signed an SCT message and my bank refused to process it, I could simply switch banks.
> credit card companies
Yeah, my bad, I should've said payment card companies / card payment processors. For debit card transactions they don't provide any benefit, they are only middlemen between me, the merchant and our respective banks.
Banks are centralized enough to be targets for government intervention. There simply aren't enough nodes in this supposedly decentralized system for the failure of a single node to not matter.
> For debit card transactions they don't provide any benefit
Banks already are a decentralized system, just not a very good one. I can send a SEPA transfer from any EU account to any other EU account no matter which banks they are with and there isn't a "SCT processing company" that handles that for me, the banks communicate with each other - the system is decentralized. But that transaction takes up to a day for pretty much no reason, so we use payment cards for most things. Those are centralized. If Visa/Mastercard doesn't want to handle my transaction, I'm screwed. If instead cards simply signed an SCT message and my bank refused to process it, I could simply switch banks.
> credit card companies
Yeah, my bad, I should've said payment card companies / card payment processors. For debit card transactions they don't provide any benefit, they are only middlemen between me, the merchant and our respective banks.