Just to add to this: trying to compile an open source Android distro is a tricky proposition that requires trusting several binaries and a huge source tree.
Moreover, having a personal route to digital autonomy is nearly worthless. To protect democracy and freedom, practically all users need to be able to compute securely.
There's a classic Ken Thompson talk about Trust where he shows how a compiler could essentially propagate a bug forward even after the source code for that compiler was cleaned up.
It's a concept that relies on a great deal of magic to function properly. The binary-only compiler we have must insert code to propagate the infection. To do so it must know it is compiling a compiler, and understand precisely how to affect code generation, without breaking anything. That... feels like an undecidable problem to me.
sure it's undecidable, you can reduce a decider for the word problem to that pretty easily, but in practice you probably only have to recognize a few common compilers to do a good enough job
