It actually depends on what are you about to protect yourself against. You don't need exceptional security preventing LE from unlocking your device if your adversary are commercial entities craving for your data to sell.
GrapheneOS believes it's nothing or everything, while the privacy is not binary.
If it's all-or-nothing then it's always going to be nothing with a phone, because the position and activity of your device are perfectly transparent to the phone carrier you're using, by mere design of being a mobile phone. They know when you're awake, when you sleep, where you are at all time, when you use a VPN and when you don't, etc, etc.
You can never hide everything, so the question is where you set the bar. GrapheneOS and /e/ have a different bar, making different trade-offs for different user base, and that's absolutely fine.
Privacy depends on fixing widely abused privacy weaknesses by patching privacy vulnerabilities and shipping major privacy improvements. /e/ is missing many standard Android privacy patches and protections. Privacy also depends on security to avoid it being bypassed. It's also missing many of the standard Android security patches and protections. GrapheneOS preserves the baseline and makes major privacy and security improvements along with being far better at patching vulnerabilities rather than far worse.
/e/ and Fairphone don't do the bare minimum to protect user privacy and security by keeping up with updates. Both are missing crucial standard patches and protections needed against many real world adversaries including widespread privacy abuse by apps.
/e/ and Fairphone don't do the bare minimum to protect user privacy and security by keeping up with updates. Both are missing crucial standard patches and protections needed against many real world adversaries including widespread privacy abuse by apps.