Linux

We may not be reading the word "mainstream" the same way here, because when you have a small oligopoly with one player at 75%, one at 15% and one at 4%... well, yeah, one of those is mainstream and one of those is not. That's kind of how being mainstream works. Hell, that's borderline monopolistic.

That's not the same as a commodity where dozens or hundreds of options are available and compete on relatively equal footing. The comparison isn't Captain Crunch versus Corn Flakes, it's Coca-Cola versus Green Cola. I can find Green Cola in my supermarket... but it sure as hell isn't the mainstream choice.

That's different to "being ready for the mainstream", though. Linux is not mainstream because it has big blockers that prevent it. The lack of readiness is a cause of the lack of mainstream appeal, not the other way around. For the same reason that Green Cola's stevia-forward absolutely wild aftertaste is a cause of its lack of mainstream appeal.

I do realize not everybody will get this comparison, but if you know you know.