Ubuntu is based on Debian, another Linux distro, and was still a huge step forward. Building on the current best in class to create something better sounds like a sensible idea.
These are all subjective terms at best. I can call Motif beautiful and no one can say I'm wrong.
That includes stuff like firmware for peripherals. So distributions further down the chain tend to include that stuff, so if you prefer to be on the cutting edge and aren't a purist about your distribution, you pick something else.
Not necessarily true anymore. They have roughly the same versions as Ubuntu, sometimes newer if you compare Ubuntu 18.04 with Debian 10 and considerably newer packages than OpenSuSe Leap 15.3 which carries some of the same versions as 15.0.
Or do you somehow believe that only a 5 word motto should explain everything to you?
I love both Arch and Debian, but I usually use them for very different things.
- X11 model is broken, people are working on Wayland to replace it, let's write an entirely solution (Mir)
- GNOME2 is working too well and people are too happy with it, let's produce a desktop environment full of bugs at least for the next 4 years (Unity) instead of fixing bugs and performance issues in GNOME3
- Package managing is just a little too much reliable, what if we forced `apt` to install random snapcraft packages instead of the intended deb packages?
To get a bit of historical perspective, Ubuntu copied what worked really well with Mandrake/Mandriva: a user-friendly user interface. But they copied it to extinguish all alternatives, which mostly worked. Nowadays, Ubuntu is only good if you can get commercial support ($$$$) to fix everything they break.