It's horrible, but could there be dual boot Graphene to deal with the ongoing Play Integrity API horror show?
Would it even know it was only half the drive if it was just a plan regular open source system?
It could be a small compartment. Plus there's the added benefit of "What Graphene phone? I don't use Graphene! See! Even your mobile forensic analyst will tell you! I swear... it should would be a lot of paperwork and hassle to make them analyze it though... Just look! It's a regular boring phone!" ;-)