GrapheneOS has a lot of security features that make it basically impossible to compromise your phone
This is very dangerous thinking. No software is perfect; there are always ways to get in.
Now, in practice most people aren’t victims of targetted attacks and even devices with dozens of known local privilege escalation and remote code execution exploits won’t ever be attacked but those who will cannot rely on “x is basically impossible to compromise”. It takes layers and maintenance to actually be somewhat secure.