Exactly what you typically see out of entrenched goliaths.
It's the same reason several of them that have tried can't catch up with Stripe, despite trying for years, despite vast resources, and despite Stripe showing them how to do it.
It's only in a non-reality-touching theory that the card companies could have done it (ie if you entirely disregard everything about them and only focus on resources and then give them attributes they don't possess). In actuality, they couldn't do it.
Microsoft and Nokia couldn't have produced the iPhone. IBM couldn't have produced AWS. AOL couldn't have produced Google. Disney couldn't have produced Netflix. Facebook couldn't have produced Instagram. Xerox couldn't have produced the Apple II. Sony and Microsoft couldn't have produced Steam. GM and Ford couldn't have produced the Model S. Boeing and Lockheed couldn't have produced the Falcon 9. Wyndham and Hilton couldn't have produced Airbnb. The taxi cartels couldn't have produced Uber or Lyft.
Culture acting as an innovation blockade is the unifying impediment between them all, not lack of resources or that something was technically too challenging.
That's not how card companies work. There's 100s of payment processor out there and the card companies let you shop around and pick one that's right for you. They do however require said processors to have large amounts of money just to access their systems.
Stripe has lots of funding to do that AND get good developers to build a decent payment processor.