I'm using GNOME on ArchLinux, at least since 2014, and I feel like I'll never look back.
The dark theme, before every other OS, looks just stunning since about ever.
The UI is buttery smooth, and the alias open=xdg-open makes me forget I'm not on macOS for the pretty much only command that I like about my macOS bash experience.
The Random Wallpaper extension makes me forget I'm not on Window, offering me amazing wallpapers from various sites curated by people, with all details when needed.
If I miss one thing from macOS, it's the Emoji widget on ctrl+command+space, something replaced by Emoji Selector extension, but not nearly as well integrated.
If I miss one thing from Windows, is just the ability to play, from time to time, whatever game, even if most things work well via Steam and/or Proton and/or dxvk.
If I could have both previous things on top of what I have daily, I'd say my perfect OS would be already a reality: blazing fast, community driven, usable in laptops, as well as Raspberry PI (or any other SBC, really), and Desktop PCs, and it's always updated 🎉
As developer, you'll indeed have always latest stable version of any package, but you can also create your own packages and publish those in AUR, where AUR is the best thing ever for community packages creation and developers.
To anyone still associating Linux to Ubuntu, just give GNOME on ArchLinux a chance, and you'll start writing posts like this one 'cause you'll be super happy, but sad if others haven't tried this combo too.
If you wouldn't know how to, give AntergOS or archibold.io a try.
I've installed these to my family and few friends, and everyone is happy.
All packages that work in Debian/Ubuntu will eventually work on ArchLinux too, so even the fragmentation excuse is not really an issue.
Now, answering to the question: why not more users?
There are still various famous "premium" softwares that work on Windows, or macOS, only.
Adobe does that, but so does Origin, EA, and many many other Games related Software Houses.
They just don't care about Linux, and not because it's difficult to distribute anything, simply because they ignore a minority of users.
There is also outdated softwar, full of bugs, security issues, yet used by banks, public administrations, etcetera ... and until they do the switch, and there are various countries where PAs already did switch from Windows to Linux, we'll still have a minority so that selling software for Linux would mean putting some effort without a certain income.
And people also keep associating the Linux world as if everything must be free while they can sell on Windows and macOS: this is simply not true at all, yet hard to drop from many people mind.
All this could change only if people started ditching the latest game, the latest software, or the latest whatever, if it doesn't have a Linux version too.
This, although, won't probably ever happen, 'cause people don't like being in charge.
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