You can try to prevent it with project structure, but even something really unified like FreeBSD ended up having derivatives like GhostBSD as well as full-blown divergent forks like DragonFly BSD that are not necessarily compatible anymore with upstream.
The actual reason for all of this is that the distro's themselves (and the BSDs) bundle 'hundreds' of external third-party system packages as first party just to get a 'basic desktop working'. I don't want to start pointing fingers at where a bug could be located at as it would be very painful to maintain and start searching through the whole Linux or BSD desktop stack. Good luck with that.
The only difference with the BSDs is that they just have a different kernel. Everything else has the exact same software stack just like many Linux distros.
Hence this, with having little to no OS fragmentation, it is also the reason why everyone only targets Mac and Windows. 'Official support' gets very expensive when 10 or 20 distros need to be tested on a CI or guides need to be updated as users tweak or mess around with their Linux distro.
This is true once you install a bunch of desktop stuff from ports and packages, however, any of the *BSDs are much more cohesive than Linux in the base system.
And I guess even the degree of desktop integration varies. On OpenBSD X11 is part of the standard installation. On FreeBSD it comes from ports.
That's the problem. There are too many Linux distributions to 'support'. From a developer standpoint. I have to 'define Linux support' and need to draw the line somewhere and pick a Linux distro and write a guide for it.
Several people will ask if their distro is also supported and another one will ask, followed by another one with the same question and then you would be updating more than 10 troubleshooting guides and maintaining more than 10 CIs for 'official' support. That's very expensive and this is why you cannot target 'all' Linux users.
On the other hand, I can support all Windows users 100% of the time. Same thing with macOS, and Haiku also has little to no fragmentation and that means I can give 1 CI per OS. Not 10 or 20. Even Redox gets it right with the same idea.
It's nice to see an open-source OS for once that has a sane desktop, usable software and is unified just like Windows and macOS.