Yes, PSD2 has driven the need for all banks in Europe to offer an Open Banking API, and with that you can have „transaction/payment initiation“. That is a „push“ transaction from one party to another. Sofort is one of the very early systems that uses that process (actually predates PSD2 by quite a bit), and did the push by screen scraping your online banking UI. Still SEPA transactions are not very quick - from Sparkasse to Solaris takes about 36 hours. From AIB (Ireland) to Sparkasse can be as short as 6 hours.
In my introduction I mentioned „real-time“, and low cost. These are important features, and driven by the technology somewhat. Usability is very important to me - hence QR codes (like Swish) and connection by shorter identities (mobile phone numbers and/or Swish like identities) are important.
A transaction initiator (Sofort) under PSD2 does require to be regulated by BaFin. It’s not too onerous, as you’re not holding the money.
An activity like PayPal, where you hold the money requires almost a full banking licence. I kind of think that holding the money makes it easier to show real-time transfer, with SEPA transfers following slowly in the background.
I think we could get the technology (and regulation) to work. That’s less of a problem.
How do you persuade 10,000,000 citizens to participate in this scheme, and use it weekly? You don’t need this number on day #1, but within 2-3 years, you’d want a consistent and regular user base.
Tomorrow or Solaris could provide a transaction hub that allows the other APIs and interfaces to be integrated, and do the kind of things that the EPC talk about in Frnk’s link.
Technology is „easy“, it’s the „adoption“ that is hard.