Fragmentation on the Linux Desktop (Is it Normal?) (Datamation)

There's one thing that we as GNOME botched completely, and that is working together with a distro (not distros, _a_ distro). I still see distros as the QA of a desktop effort (while upstream is the R&D part), and GNOME essentially does not have any QA at all. (To open parentheses a third time, this failure is also what lead to the GNOME OS effort - if we can't get distros to cooperate with us, we'll just do our own!)

What I'd have expected to happen long ago is that a distro provides a build farm that compiles per-commit packages that can be installed and used by anyone alongside the regular packages. I'd have expected these packages to work so seamlessly that they make jhbuild completely obsolete.
I'd also have expected the build farm of the distro to be a vital component of upstream development in that it is used to find build or test failures or even performance regressions and notifies the upstream developers of those, so they can be fixed in a timely fashion.
Last but not least I'd have expected the distro to cooperate with upstreams on the controlling and management effort - that is maintaining, analyzing and guiding bug tracking, proposed features and the overall user community.

All the distros do this to some extend, but they all do this in spite of upstreams, not with them. In particular the GNOME vs Ubuntu story is a good example of this. GNOME tries to do QA these days and fails as much as Ubuntu, which tries to develop code on its own. And worse off are all the people who have to use the resulting product(s).