Revolut is specifically banning #GrapheneOS by checking for the build machine hostname and username being set to 'grapheneos'. We've changed these to build-host and build-user. Combined with another change, this allow our users to log in to it again until they roll out Play Integrity API enforcement.
There's no legitimate excuse for banning using a much more private and secure operating system while permitting devices with no security patches for a decade. Meanwhile, Revolut's shoddily made app tells users they're banning GrapheneOS because they're "serious about keeping your data secure".
Revolut's app will stop working against once they start enforcing having a Play Integrity API result showing it's a Google certified device. This is not a security feature but rather anti-competitive behavior from Google deployed by apps like Revolut wanting to pretend they care about security.
Revolut uses a bunch of shady closed source third party libraries in their app and it's one of these libraries banning GrapheneOS. These libraries are a major security risk and put user data at risk of being compromised. Revolut is not taking user security seriously at all and is cutting corners.