A new European initiative dubbed UnifiedAttestation aims to build a free and open-source alternative to Google’s Play Integrity checks. The initiative is backed by smartphone maker Volla, while other partners include /e/OS maker Murena and the team behind iodé OS. The feature will be distributed under an Apache 2.0 license.
They are if banks don’t allow their apps to be functional on grapheneos.
I have never had an issue with banking apps so long as exploit compatibility mode is enabled for them.