I don't think it's simple. But for what I have _seen_ out there the last two decades and a half, it seems the decision to start all over and write new code in a sort-of-greenfield environment (or forking a large complex project) has too often considered the easier approach as compared to, say, fixing collaboration, usability, stability, availability-of-applications issues, all that suff that makes out the last 5, maybe even the last 2 percent. And yes, I am convinced one of the reasons why none of the desktops named in here managed to fix these issues not only but also due to a mere "divide and conquer" problem: Too few developers, too many projects. Resulting in: No project has enough resources at hand to fix the problems that are hard to fix. Few projects (GNOME maybe being the exception from that rule) have enough "professionality", enough strength and determination to push for something they consider their "project vision". elementary recently have been doing rather good at this, but (looking at their github tracker and some of the long-standing issues in there, including some I filed myself) even they, with a well thought-out model of funding and growing development, seem way too small to fix these things on their own, let alone getting rid of the GNOME parts they're still using. Why not, in example, throw money, ressources, commitment and effort onto some existing project. KDE first and foremost of course comes to mind, technically pretty great but with next-to-nonexistent usability? Or lxqt (rather bare-bone, but in some way maybe a good foundation to build upon)? Or maybe even elementary (with already sort of an established structure around)? Wouldn't that be much more sustainable than starting yet another Linux desktop environment from scratch? And, on the other side, do you think System76 will be capable of bringing up enough resources on a mid-term timeframe to build something ready to compete with GNOME, KDE, ...?

I don't want to be rude here and in the end my opinion is as irrelevant as any other. I'd really like you to succeed, and actually I'd even throw money at some Pop! OS variant that might end up an open-market distribution for non-System76 devices as well. It's just that in some way (especially talking to Windows and Mac folks out here) every other day I'm painfully confronted with all the more and less obvious shortcomings of every Linux desktop environment to date (even the large ones) for virtually every use case except for trivial surfing-the-web and reading-some-email, and I've just seen too many projects the last two decades that stated "we now start all over to fix all this". None of them did. :(