The issue is that the digital tap-to-pay cards are actually reissued cards with their own unique numbers. They also require significant security measures to protect from cloning attacks.

So banks need a party that they can safely issue a digital card to, knowing that the card data will be stored safely.

Even a FOSS app that covers all the user's needs is going to have a lot of trouble actually getting a card loaded into it under current standards.

I hate to say it, but crypto wallets are likely the closest thing we're ever going to get to a FOSS tap-to-pay system. Banks are inherently corporate and capitalist, so it's not really in their nature to make things open source.

Perhaps if there were an industry standard for issuing digital cards, instead of banks partnering with centralized wallet apps, we could procure our own digital cards to load onto our phones and watches, or integrate into other devices. But that's a whole other battle that nobody is fighting right now.