Graphene modifies AOSP for much more security.

E.g.

• you can disable USB data at a hardware level
• Receives Kernel updates even faster than Google’s phones
• uses a different memory allocator, hardened_malloc
• changes the way zygote launches apps, so ASLR actually works
• doesn’t allow apps to ptrace themselves
• disables JIT per-app
• disable network access per-app

I dont think e/OS is as security oriented, more privacy oriented

The only way they can do this is by removing most features, or simply not connecting to the internet.

Even “American” SoC suppliers have a majority of their programmers in China