The Hobbyist

Some apps will rely on Google services to determine whether they are running on a “secure” device (ie determined by Google). This is refered to as hardware attestation. But there is a Google version of it and a generic version of it (which is implemented in GrapheneOS). If the bank relies on the Google version, it will fail on GrapheneOS, despite actually having hardware attestation.

You can read more about it here : https://grapheneos.org/articles/attestation-compatibility-guide

https://serverpartdeals.com/

I’m not sure because a bank being absent from such a list could either mean the compatibility is known to be functional or unknown. And that’s very different and I would argue a very critical difference.

As a user I would definitely care most about a list of functional banks and that is what we have. What you propose, while it has its value, would not be actionable to users due to the ambiguity I raised above.