Even if everything is imperfect, some things are more imperfect than others. If each component that makes you vulnerable has a given percent chance of being used against you in practice, you're better off with one than six, even if you're better off with none than one.
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.
http://cs.bell-labs.co/who/ken/trust.html
It's a fantastic concept.
For example the only closed source component that I use is the NVIDIA driver, but I could use Nouveau, with lower performance.
The real problem is caused by the hardware backdoors that cannot be controlled by the operating systems and which prevent the full ownership of the devices, e.g. the System Management Mode of Intel/AMD, the Intel ME and the AMD PSP.
The real problem is that most people don't have the knowledge to compile a distro and load it onto a phone. Most people don't even know that's a possibility or that the distro on their phone isn't open source.
So it would be better to say "this has been a risk by using modern technology".