One of your statements is what I feel is more of an obstacle to mainstream Linux adoption than anything technical. There's a lot of distros out there with a lot of churn. Not a bad thing if you are a geek and have the time to try out a variety of distros, but Grandma is just going to want something that Works.
Similarly (possibly because of this churn?), I feel Macintosh and Windows are ahead of the game compared to Linux for providing more usable documentation. Linux forums likewise tend to be very techie oriented; the general consensus I get outside of the computer world is that this heavy technical nature is very off-putting ("arrogance" and "snobbery" are a common complaint).
Linux still has some problems technically (has audio gotten any better, for instance? ALSA / Pulseaudio was messy compared to Windows / Mac last I looked) but I think a lot of the obstacles to adoption are more non-technical at this stage. Google after all made a Linux kernel OS mainstream.
Good points. Although I do have the impression that, because of the rise of less tech-savy people using Linux, there also is a rise in forums/documentation which is more aimed towards those users and hence easier to digest in most cases. I mean, basically I am one of those users since I don't use linux daily and apparently not enough to get solutions to common problems wrong stuck in my head, and I do have the impression that if I have problems these days the answer is in one of the first search results encountered. (alternative explanation is that search just got way better :)
Unfortunately that also means sooner or later we might find ourselves in the too-many-unrelated-crap-answers situation which exist now already for a myriad of Windows/Mac problems. Distilling the correct answer for your specific problem where the OS tells you 'error C0000005' or so seems to get harder every year. Add 100 different distros to that and it won't get any better. Though sites like stackexchange seem to do a pretty good job of keeping it to the point.
re: Audio: I actually asked the same question here last year or so and IIRC the answer was 'still the same mess'
Similarly (possibly because of this churn?), I feel Macintosh and Windows are ahead of the game compared to Linux for providing more usable documentation. Linux forums likewise tend to be very techie oriented; the general consensus I get outside of the computer world is that this heavy technical nature is very off-putting ("arrogance" and "snobbery" are a common complaint).
Linux still has some problems technically (has audio gotten any better, for instance? ALSA / Pulseaudio was messy compared to Windows / Mac last I looked) but I think a lot of the obstacles to adoption are more non-technical at this stage. Google after all made a Linux kernel OS mainstream.