Sure, you're right about that under the hood, but...
If it's to gain mainstream success, yes, we need a big, well supported distro that everyone's throwing their weight behind. Ship it on consumer machines (and have some features for that), ship it on business machines (and offer some remote management capabilities), get the name out there, give it some shine, etc. Ubuntu's actually coming along quite decently in this regard - apparently they have an enterprise version (probably paid) with the management features, along with their free consumer one. Bingo.
Let me put it this way... Windows is Windows, on any machine. OK, there's a few newer/older versions in circulation and they keep changing the interface, but anyway. There's also Mac OS X, which is that. And then there's linux - how many linux distros are there, all slightly different, some more confusing than others? For the average person, that has to be confusing. What's an OEM supposed to ship? Etc. I'm not saying you shouldn't have other distros out there, but I am saying there should be one major one that everyone supports, that's what you mainly get if you buy a linux machine, etc. Asking my grandmother to download Firefox doesn't mean one of the many oddball variations (with none that stand out), after all - it just means Firefox, that well known browser, and even she knows what that is.
Side note... I downloaded Ubuntu 15.10, and stuck it on an 8000 elite/E8400/Q45/Geforce 310/8GB machine (same test-bed I've had for the last several months) - yes, I know 14.xx is the LTS version, but I'm curious. The 8000 itself is on Ubuntu's certified list, and is pretty standard Intel hardware for the time (funny, since it's from 2010, and most of the list is Haswell/Broadwell/newer hardware), but the GPU option isn't. Installed that, let it download 3rd party stuff and updates during setup, loaded up Chrome, and switched the driver to the tested nvidia binary one instead of the x.org one. It's kinda funny that people complained when they added the amazon stuff into the search menu - it's annoying, yes, but easy to disable and nowhere near as obtrusive as 10. Man... Plus, the UI is quite logical here - everything's pretty much where I'd expect it to be, the settings panel is simple and easy, etc. And it turns out that linux distros work best if you use their included drivers (i.e. use the binary driver built in, don't mess with nvidia's download) - the opposite of what I do on Windows.
Now for my usual test... lots of Taylor Swift youtube videos. (I may be a Swiftie... maybe...
) I'm getting slightly high CPU use (50% for 1080p, 25% for 720p), but that's just VP9 being its usual self. Totally smooth playback, hasn't crashed yet, playing 1080p (on a single 1280x1024 monitor... I'm lazy, and that monitor was closest to the machine). So far so good, although I haven't tried vmware WS. Next step is plugging the big 30" monitor, mouse, and keyboard in, and running it as a daily driver for a bit. Pretty much everything I do runs on any desktop OS anyway (save for a few tools like Solidworks and paint.net), since I moved to gmail and Libreoffice a while back.
Side note: Whose idea was it to frame the Taylor 22 video as 4:3, and make it into a 16:9 file? This looks really dumb on a 4:3 (or 5:4) monitor...
Edit: I had another thought about fragmentation - Android. Any given apk will run on most Android phones out there (unless they're on an ancient version), but people have different versions of Android, different versions because of OEMs, different preinstalled software, different UIs/launchers from the OEMs, etc. That doesn't help brand identity for the Android platform, for one.
Edit edit: I see you have a Dell M4800 - what sort of hybrid graphics does it have, and how well does Arch handle those for you? I keep wondering how well hybrid graphics work - sounds like muxerless/newer ones are better - but Ubuntu does actually have some hybrid GPU systems certified. (AMD anyway, not sure about nvidia.) Maybe it's time to put Ubuntu on the zbook and see if I can use the GPU for Solidworks through VT-D? Or is that crazy talk? (Never seen VT-D used for anything consumer, though I do have it.)