Its an issue that, currently, banks have to resolve by either developing (see certain EU banks that have done so) or supporting an NFC card management app that doesn't require the highest level of the google play security thing to function.

I doubt EU legislation can fix this, and I doubt Canadian banks will care enough to do anything to support anything beyond apple pay and google pay.

What you use for home automation if you're into open source and security?

I can't imagine grapheneos shipping on a phone without NFC.

...I wish I had the money to play with homeassistant for random things.

The apps that enable tap-for-payment ask your bank for permission and some security details to activate using cards for NFC.

In North America, banks won't give that permission/security info to any android app but google pay, and only if the play store verification thing says the OS is fully secure - and google pretends grapheneos doesn't hit those security metrics.

So yes, NFC is how tap-for-payment works, but unless NA banks implement it themselves, or trust a 3rd party that isn't google to implement it, grapheneos phones are blocked from using the tap-for-payment functionality.

NFC is just the technology that tap for payment uses, but there are other use cases for it.