Canonical is patching, more than Debian. Which is causing own specific bugs. Upstream developers don't like that. The attack through the xz package is just one last example. Fedora also patches but limit it to small changes e.g. transparency for the Gnome-Terminal.
But Canonical is not just patching. Their launching counter-projects:
* Mir instead of Wayland
* Unity instead of GNOME
* Upstart instead of Systemd (Upstart is older but just SysVInit with patches)
* Snap instead of Flatpak
Canonical always tries to push own stuff and harms the community. Usually Red Hat and the community oppose and win because:
* they are better
* and stronger
What Canonical does well is shipping closed-source drivers (a thing which we don't want) and libraries for codes and their installer is neat. Fedora instead requires you the add RPMFUSION but delivers a clean GNOME, fast updates and don't try to ship weird stuff. I install Fedora for all regular systems which shall require little to no maintenance. Especially for non-technial users.
For professional task and my very own system I prefer Arch. They only patch when it is necessary, usually upstream patches. If you want a terminal with background transparency there are packages with patches in AUR.
The distribution should be the choice about installing and package-management, the software (i.e. GNU and Linux) shall be in general the same. It shall not matter "which" Linux you're using.
I agree that Canonical have definitely had a history that feels like Not Invented Here, but so what? That's the real glory of this system, that we can pick out parts and try to do something better.
They've attracted a lot of ridicule from users, members, upstream, but it's their house, their engineering effort. Let's laud their attempt.
Mir, Upstart, Bazaar, AppArmour were all projects that started at the same time as the eventual "winners". It's not wrong to experiment.
Let's also not pretend that upstream always gets it right, or that they do things in concert with the wishes of their users (ffs Gnome).
