Not only in that case.
Your ability or interest might change. Like what happened now with NSA backdoors getting more publicity, the Linux code is getting more reviewed for their backdoors, even after being in use for several years. If the source were not available, it would be a lot harder to check.

About "non-code submmitting users", I don't think they are the ones who should audit it. You can trust someone who does submit code, or you can suddenly gain interest in security and start checking it, or even pay soomeone to do it. The thing is that it's possible.

This is why it's a lot better to think in terms of Free Software and not open source. Technical advantages are hard to value if they are not used. Freedom is a lot easier to understand. You have the freedom to use the code as you like, share it and whatever. To illustrate the importance of freedom vs its exercise: lots of people don't want to, or don't have the money to travel outside their countries, but we don't like to have that possibility restricted.

1 - Citation needed. In the sense of open source being easier to debug than proprietary code, it's undeniable.
2 - Citation needed. That strawman is getting old.
3 - True. It does mean anyone _can_, not that anyone _will_ . That's very valuable by itself. You can trust the vendor for example, but have the possibility to stop trusting them. Don't you prefer to be able to find backdoors vs not being able?
4 - Citation needed. Same as 2 -

You make sense. But it's a very subversive thing to say, for an American.
Your point is that if someone is to be rich, then someone else needs to be poor.
Plus, you don't really care about poverty, you just care about your standards of living.
But following your ideology, if one were to get rid of poverty, one would first need to get rid of the rich. You can't have everyone living above poverty levels, if you don't first get rid of the rich.

You discovered marxism. Congratulations. And good luck implementing that in the United States.

Linux _is_ a kernel. Everything else you are talking about is mostly the GNU part of GNU/Linux.
Android has the same amount of Linux than any flavor of GNU/Linux, so the GP is right, even though he uses the wrong terms.

Cool, as long as they don't harm me in the process.

RMS doesn't use that word, "open" a lot.
Doesn't use "greed" a lot.
Those are probably your preconceptions of what he says.

RMS usually talks about freedom, as in not giving away your freedom.
DRM requires you to give some other entity control over your devices, more than what you have. That means giving away freedom, and that's why he is against it. I agree with him, also.