I'd second your assumption. Geary, MegaPixels (the camera app), Phosh (one of the few window managers), the modem firmware, and more are mostly shared between all the distros. Doubly so for upstreamed SoC firmware, battery efficiency improvements, and more that I'm sure I'm overlooking.
Frankly, it makes me question anyone who says desktop Linux is divided because we have options - at this point, it's more like there's no large corporate backer with a vested interest in making the desktop experience mainstream.
Asking for clarity since I'm one month into my Linux journey:
Are you saying that most of the distros are really just more surface level changes rather than deep "divisions"? I've been struggling to understand.
They ship different things out of the box but can largely use the same exact software. They may update at different rates and thus have different versions of things. They are not entirely different operating system like Mac OS vs Windows.
Mostly. There are a half dozen different desktops to choose from. Same for ways to package software. Most of what a distribution does is make some choices and configure it. Most distributions learn from each other in some way. Most distributions fix things upstream so that other distributions can take advantage for their useful changes.
Good catch, thank you. While Steam currently prints money AFAIK, they're simultaneously 30 years behind Apple and Microsoft (as far as being the driving force of a desktop) and the reason Steam (and gaming on Linux) has come so far, so fast recently.
Frankly, it makes me question anyone who says desktop Linux is divided because we have options - at this point, it's more like there's no large corporate backer with a vested interest in making the desktop experience mainstream.