Yes. They (cellebrite) don't mention GrapheneOS support very loudly because it's poor. They can't decrypt one that's BFU (Before First Unlock), not even by brute force if it's a 6 digit passcode apparently. Don't know if they can get data from an AFU GOS pixel. A year ago when their internal docs leaked, they also had no support for latest iOS at the time, but had brute force support for older versions as long as phone itself wasn't too new and had AFU access without brute force for even older versions.
Moral of the story: if there's a chance police might take your phone to investigate for a crime you hopefully didn't even commit, shut down your phone completely - the 5x power button trick on iOS disables biometric unlock, but the device itself stays decrypted and thus more vulnerable. Also keep your OS up to date.
If you've got a phone that's neither iOS nor GrapheneOS, it's probably pretty much Swiss cheese anyway. IOS isn't as good as GrapheneOS either, but it offers some protection against Cellebrite if up to date and BFU. But if they keep your phone for long enough (months, years), they'll get it unlocked because you can't install updates that would patch any newly discovered vulnerabilities and one day they'll find a BFU unlock for it, probably.
