I agree, we can say a lot of bad things about Google when it comes to privacy, but their security is quite ok. Verified Boot is also done at OEM-level:
Verified Boot
Verified Boot strives to ensure all executed code comes from a trusted source (usually device OEMs), rather than from an attacker or corruption. It establishes a full chain of trust, starting from a hardware-protected root of trust to the bootloader, to the boot partition and other verified partitions including system
, vendor
, and optionally oem
partitions. During device boot up, each stage verifies the integrity and authenticity of the next stage before handing over execution.
In addition to ensuring that devices are running a safe version of Android, Verified Boot checks for the correct version of Android with rollback protection. Rollback protection helps to prevent a possible exploit from becoming persistent by ensuring devices only update to newer versions of Android.
In addition to verifying the OS, Verified Boot also allows Android devices to communicate their state of integrity to the user.
When the e.foundation starts to work with OEM’s that provide /e/ on their phones they will probably talk about verified boot.