Santander uses Open Banking too, so I'm still wondering what's the benefit?
It does and it's part of the eco system.
You might have seen the benefits without actually seeing them. There's a number of benefits already in place for us.
Aggregation of accounts into a single app - adding your barclays, or lloyds of whomever accounts into your Santander app.
The Openbanking infrastructure is much than just accounts and payments; It's lowered costs for the basic user, transaction costs are down as part of the implementation of OB; Such as the ability to pay banks in their standard currency providing they have a presence in the location you want to pay from. e.g. if you pay via pounds, to a US bank (which has a presence in London) you save on the exchange fees.
Surcharging of most credit card payments have gone down as a result of the extra competition in place now.
You have more consumer rights, Reduced Liability (reduced Cap of quick payment). Right of Recourse (SCA / Strong Customer Authentication). Multilateral interchange fees (charging cards excessively for us – capping surcharges imposed by retailers 0.2 Debit, 0.3 CC)
The banks now have opened up their APIs to fintech companies, meaning they can get creative with what they want to do with access to those APIs. Theres no longer a closed ecostructure.
SCA (strong customer authentication) is now mandatory, meaning you have to have 2 of three elements (PIN, biometric, possession).
Presume that's enough for now?