There's no tension between the security of PayPal against bad actors and support for GrapheneOS. GrapheneOS preserves the whole standard security model and greatly improves security. It's far more secure than anything permitted by the Play Integrity API device or strong integrity levels.
Thankfully, PayPal hasn't banned GrapheneOS and their app still works on it. They accidentally broke compatibility with our secure app spawning feature which has a per-app toggle to disable it along with the other exploit protections which can cause compatibility issues.
There's an overall per-app compatibility mode toggle instead of users needing to figure out which protection is an issue but it's best to figure out the minimal workaround after determining that works.
Thankfully, PayPal hasn't banned GrapheneOS and their app still works on it. They accidentally broke compatibility with our secure app spawning feature which has a per-app toggle to disable it along with the other exploit protections which can cause compatibility issues.
There's an overall per-app compatibility mode toggle instead of users needing to figure out which protection is an issue but it's best to figure out the minimal workaround after determining that works.