Now, don’t get me wrong, I like the premise of GrapheneOS. The security features it offers are great. However, you’re sacrificing useful hardware features by using it.
Currently, the only phones that support GrapheneOS are Pixels, which lack the microSD card slot, dual sims, and a HEADPHONE JACK! To me, those features are not worth sacrificing for a little extra privacy.
Compared to LineageOS, however, they support a broad range of devices, even pixels. I can look through their supported devices and find one that has a headphone jack, microSD card slot, dual sims, etc. Yes, it’s less private than GrapheneOS, but it’s still more private than stock android or any of those other OEM roms (OneUI for example).
You can still keep some privacy using LineageOS while preserving functionality with projects like MicroG.
Overall, I think for the time being, unless you are really paranoid or live in a anti-privacy area, LineageOS is the better OS to use than GrapheneOS due to still gaining some level of privacy while preserving useful hardware festures. Once GrapheneOS branches out from Pixel phones, I might change my opinion.
A few things to add to this:
Graphene adds new permissions: network and sensors. So if you don’t want an app to access the internet, it can’t.
Graphene also allows you to install Play Services, Play Store, and Android Auto, but sandboxed the same way that any other app is. For example I find Android Auto very useful and that requires Play Services, and the fact that I can get easier push notifications and the security of Play Store is nice. This also minimizes incompatibility for apps that use the Play Integrity API. If you’re going to do this I’d recommend making a burner Google account from Settings so it will allow you to use a VPN connection and not ask you for a phone number.
GrapheneOS removes Google’s location services and uses their own.
GrapheneOS supports multiple user profiles, and apps can be pushed from the owner profile to other profiles. So you can havw some profiles with or without Play Services, further sandbox sketchy apps you’d rather not have to use but are forced to, separate work apps, have multiple accounts for apps like Signal that only support one account, etc.