Gnome, Unity, KDE. I couldn't care less. They all let me launch apps and switch between them quickly and easily. That's all I need from a desktop environment. I don't understand why people feel so passionate about them.
For example with KDE activities you can save states of your desktop (which apps are open, their position on screen, their open tabs, files etc) and restore them whenever you want. So you have ready layouts for your usual tasks and you can start/stop or switch between them in seconds.
Another small example that exists since KDE 2 maybe: you get a clipboard with history. How one may live without it?
Also you get all the small perks like easily setting your keyboard layouts, shortcuts etc.
You get a very fast search utility. Navigating to a file through your file manager is so ineffective when you can type a few letters and find the exact file or folder you need. Searching through your email with gmail (or better) speed from your system tray without having to go to your browser is so useful.
There are a ton of small nice apps, like a ruler or a color selector or a screenshot utility. You may connect to a VPN with exactly two clicks or send your music from your speakers to your bluetooth headset.
Your music or video will autopause when your Android phone rings. You get notifications synchronization with your Android.
Your archive utility can preview any type of file even with color highlighting if it is code. Your apps can edit directly any file on remote file systems (even ftp or ssh).
There are so many things a well designed desktop environment can do for you.
It sounds like the setup you describe is only possible with a huge amount of configuration.
With enough configuration, Emacs could do all those things too.
The only one it doesn't do by default is the Android integration but you only need to install kde-connect and pair your phone. Kde-connect will probably be part of the default installation in the near future, so it will be out of the box too.
KDE always had such cool features. For example when audio CDs were still a thing, whenever you inserted an audio CD in your drive and open it in KDE's file manager it would show you folders with mp3 and flac versions of the songs. Once you tried to copy them, KDE would rip and encode them on the fly for you!
I think it probably confused a few people when it looked like their Red Book audio CD contained folders, one of which contained Ogg Vorbis files, ready tagged.
I had actually forgotten about this, thanks for the reminder!
There is a tool called glipper on the GNOME side that does this. I don't know how it fared in the GNOME 3 / Unity conversion though. I do remember that at one point it only needed a systray + GTK, but then they made it dependent on some GNOME stuff so I couldn't use it in a more stripped-down environment (e.g. xmonad + alternate systray).
For Unity I'm probably simply not in the target group, I don't like it.
I left KDE many years ago because I found it buggy and bloated. Maybe it's time to give it a look but I'm happy with my Gnome Shell (in a very nearly out of the box configuration).
I was initially annoyed by Alt+` to switch windows within a program group but now I find it useful
Personally, I left Gnome because it felt unrefined and designed for a device other than a conventional laptop (i.e. one without a touch screen). I left KDE many years before then because I found the UI too busy, but they seem to have left that behind them so it might be time for me to take another look as well.
On the other hand, the persistent sessions/activities in KDE someone mentioned sound intriguing.
What did you switch to?
That's what I was trying to say. I'm sure it works for many, but it doesn't work for everyone. That's why people still "care" (if selecting one or another is caring).
I think people still like DE because they try to make mouse UX fancy. If you're used to keyboards, dmenu is almost all you need. I'm sure even casual users or noobs would love it.
You're going to reply "but these things work outside DEs as well" - they do (though only to a degree), yes, but these systems were conceived and standardized in context of the desktop environment projects, and that's no accident. As communities they attract developers and spawn efforts to make things act in concert. And they continue to be the breeding ground for more goodness of that same nature.
So even if you're not fond of what you think of as DE UI, you have benefited from their development, and continue to benefit from them. The DE communities continue to shoulder this kind of work almost exclusively.
My point was that the DE development and user community has greatly enriched the ecosystem in general, and continues to do so. I'd like it if people who aren't fond of DE UIs (which, again, is fine by me) would acknowledge that more, instead of disparaging DEs as they often do. It shows a lack of understanding of how things work and flow in the greater community. The reality is that your experience outside the DEs would be far poorer today if the DEs didn't exist, because it's been and continues to be the DEs that drive many platform-y developments that enhance applications. Know whose work you rely on and what motivates them.
But of course, I can provide some concrete examples of shared global state popping up in my own workflows:
* The KDE platform has a framework to manage user search engines. You can manage them in System Settings, Plasma's control center application. Many KDE Applications will alow you to select text and hand it off to a search engine from the context menu (along with providing an entry point into the management UI, which can also run outside of System Settings; this takes care of making it work outside Plasma). The Plasma Desktop shell does the same, though, with its Run Command box, which is one keyboard shortcut away, also being aware of search engines and being able to start searches.
* The shell similary exposes things like favorite file system locations, which also pop up in file dialogs and file managers, in Run Command, the launcher, and other places.
* The KDE platform has the best support for international calender systems and calendering data like holiday information available in free software today, and the clock/calendar thingie you can stuff in a Plasma panel reflects those abilities, as do the applications built on the same platform.
And many other little examples broadly in the same vain. As you can see, the pattern is: The platform can do a lot, and there's some benefits to the shell being built on the same platform as the applications, at least for me. That doesn't need to be the same for you; you may interact with your computer in different patterns. You still get to enjoy the applications.
KDE is blasting away any other "user interface shell".
If looks didnt matter, stop shaving and getting haircuts, and other pruning activities. KDE is best looking user interface which exists today. And it has just gotten better.
Looking at something like Windows 7 or 8, is vomit inducing.