You’re implying that to even install the simplest of programs, I’d need to read and understannd many thousands of lines of code, starting with the FOSS project itself and then spidering out to every dependency. This speaks nothing of the fact that it may be written in multiple languages, some of which I am not familiar with, and even if I am, code can be written in ways that’s almost impossible to understand. This might take a week for a 200 line project.
Reminds me of when my employer said they were going to stop using open source software until a team had vetted it completely. Lol, once they talked to engineers that idea died immediately.