Look into profiles. You can change your phone to a different profile that has nothing incriminating (or private) on it. Then switch back when you board your plane or when you have finished going through security. The authorities may or may no be up to date with knowing about them, but I doubt it. The ones who would know are the ones who do forensics on tech, but not necessarily TSA or other airport security detail.

You can customize what's on the other profiles, such as limited or no access to certain apps, etc. You can even make it so you have a fake photo gallery and fake contacts. Anyway, YouTube channel with tons of GrapheneOS pro tips on it called Side of Burritos has a whole series on guest profiles and Google Play sandboxing: https://www.youtube.com/@sideofburritos/search?query=profiles