It verifiably does not on open source and free android roms like Graphene. Unsure where you're getting your info.
No one even brought that up. We're discussing being able to install unsigned/self signed APKs. Please stay on topic and take your strawman elsewhere.
I use GrapheneOS with the Dutch ASN banking app and the ICS credit card app. Pretty much all other major Dutch banks work as well.
https://privsec.dev/posts/android/banking-applications-compa...
Google Pay does not work, but some other NFC payment apps do (e.g. Curve).
[citation needed]
I run GrapheneOS and use several US-based banking apps. I'll not name them since I don't really want my HN account associated with my financials in any way, but I've got a mix of well-known national bank apps and smaller local credit union apps working.
I'll admit there is a single institution's app I've found that doesn't work, but that is just one of several that I use.