Dumb title but I didn’t know how else to put this into words, bear with me for a sec - I am not just looking for the definition.
Years ago I tried Ubuntu which used GNOME and assumed that its desktop layout was “the default” GNOME. I later tried PopOS which also uses it and it was the same, and when eventually I installed Mint I saw that it’s still fundamentally the same with some slight tweaks or different tools.
Well, few days ago I installed Bazzite (Fedora) which is also GNOME. It doesn’t look anything like anything I’ve seen before, either in terms of mindset or technical layout. I’ve gone from an admittedly old-fashioned, but efficient and reliable!, layout and workflow to something that reminds me more of an apple product - its stylish, minimalist yet inefficient and utterly frustrating to get anything done with because of how opinionated it is.
When searching for common problems I often found comments saying stuff like “but try it out! it’s in the spirit of gnome, it takes a while to get used to it but the philosophy is valid” and frankly I don’t understand anymore what exactly gnome is and what are its design principles, if there even are any and every distro just does whatever the f it wants and call it “a gnome experience”.
So, GNOME, KDE, XFCE, LXQT, Cinnamon, MATE, Budgie, Pantheon and a bunch more are what are called desktop environments.
They essentially provide a desktop experience through a framework and development guidelines. Most of the development teams provide a “default” desktop environment setup that should be pretty standard across all distributions. However, each of these distributions want to stand out by applying their own branding. They’ll add customized icons and themes and as much as adding extensions to modify desktop functionalities.
Other than GNOME, most of the desktop environments will change minimally across distributions except for some theming and icons. But because GNOME is the standard default in most distributions, like Ubuntu, Fedora/RedHat, OpenSuse, and many more, they tend to spend more time and effort into making it look “their own special way”.
The other issue with GNOME is that the pure vanilla desktop experience is practically unusable by many users’ opinion. It’s extremely minimalist and it’s quite different from the standard desktop paradigm that most people are used to with Windows or even Mac OS. And it’s easy for new users to get lost. So most distros add some quality of life extensions like application bars, menus, system trays (yes! because there is no system tray by default) and other things to make it easier to use. That’s why your experience has been different across so many distros.
On top of that, GNOME’s desktop environment has changed a lot throughout its iterations. The first version followed a more Win95 type desktop with an equivalent to a Start menu. Then version 2 changed to offer a different desktop with two bars by default: one at the top with the applications menu and system tray and one at the bottom as a task bar. This was customizable. Version 3 changed dramatically and became more minimalistic with a new paradigm and it made users very unhappy. Then finally v4 came out and pushed v3 a little further, minimalizing the desktop even further. And all of this came with major changes to the application frameworks and guidelines. You can see the differences in this video.