Government digital signature app fully trusts GrapheneOS since it uses hardware attestation rather than Play Integrity, so I have access to all government services.
My bank's app runs on GrapheneOS but doesn't fully trust it. Device is labeled as insecure, biometric login is disabled, and transaction limits are significantly lower, but is otherwise functional for daily use.
Bank accepts logins authenticated with government digital signature app, so I can use that to login into the bank's web app and make transactions without reduced limits there.
The bank's app relies on Google Wallet for contactless payments, which doesn't work on GrapheneOS, but it looks like there are workarounds for this like Curve Pay that do work on GrapheneOS. Haven't tested this myself, since I just use a physical card.