As blind as my belief that Asia exists, because I haven't personally navigated there. Hell, I've used electricity (using it right now), but I couldn't do the experiments you need to do to get myself to an 1850s level of understanding of how it works, much less our current level.

I trust that Linux has a process. I do not believe it is perfect. But it gives me a better assurance than downloading random packages from PyPi (though I believe that the most recent release of any random package on PyPi is still more likely safe than not--it's just a numbers game).