It is painful to even try to use. It forces so many unnatural behaviors, in favor of... I don't even know why. It's not elegant, it's not pretty, it's not fun to use.
It is bad. Horrendously bad. And suited to the tastes of little more than a very small handful of people, who probably open a browser and read email, and do little else, except maybe script shell commands on the rare occasion.
Their decisions arbitrarily imposed on many, who likely still use the distro, simply due to ease of installation (and probably no other reason), and then shoulder the burden of routinely overriding the default install configuration immediately.
I still prefer Unity nowadays. It's simple, it's fast and stable (at least for me), and it reminds me of OS X (which I also like).
Everyone who runs Linux at my job uses it. No one had to be taught how to use it. No one has had any issues with it or complains about it. It just gets the job done.
I totally get that not everyone likes it, but Canonical is targeting a general audience and I think they're doing a good job. If you don't like it, just apt-get something else. It doesn't need to be super customizable and cater to everyone. Let them focus on their core features for their primary audience.
While lowest common denominator UIs are great for simple tasks performed by novice users, so much more can be accomplished by even putting in a little effort. I mean you did take the time to learn a programming languge, correct? Or was your programming language so natural you never had any questions? Did it just work without any effort?
Or are you implying that a GUI is a distraction? That it provides no benefit and something like a tiling window manager or other system can't give you any productivity benefit? I'd find this hard to believe.
Unity is simple and it doesn't try to be the be-all and end-all of my computer use. Unity seems to be designed by people who understand that the purpose of a desktop environment is to facilitate launching other programs and perhaps moving their windows across the screen a little bit, and that's it.
I am a former KDE user, and I used to spend hours and hours on end tweaking my KDE configuration. Finding that perfect equilibrium was a quest without end, but the abundant opportunities for shaping the DE to my liking didn't make me any more productive.
Switching to Unity was a liberating experience. Suddenly, I could not do any of the things that KDE allowed me to do...and I didn't suffer any ill consequence as a result of that. Rather, I discovered that all I ever needed from the desktop environment was to let me run Emacs and Firefox. Everything else was, and always has been, superfluous.
On the other hand I'm worried about the resources invested in this project, instead of stability or performance improvements in Windows. In the long term I'm worried about Microsoft's monopoly.