Armbian is open source software and provides pretty solid build framework that produces easy to maintain and stable software. Most of the maintainership burden and expenses are on Armbian developers. You can sleep well even you don’t support them. Even you will use some other modern OS its highly possible you will be using their work.
You can use this framework and fix your specific low level problem … and rebuild image in no time. Where is the problem?
Debian or Ubuntu has nothing to do with detecting screen resolutions. Low level software that is not part of Debian.org or Ubuntu.com does. I think this should be well known to most of the people that uses those boards by now.
You can assemble Armbian with a stock 4.4. kernel and detection will work the same, so you can say Armbian doesn’t work. It works exactly the same. But I see that is not what you want. If you want to have the same functionality in modern kernel, read this:
https://docs.armbian.com/User-Guide_FAQ/#why-does-hardware-feature-xy-work-in-old-kernel-but-not-in-more-recent-one
DIY or hire someone. Then send a patch. You have the problem - stop begging people to fix problems you have.
On a side think about wonderful work Armbian provides for you. How much burden was already taken away so you don’t need to throws hundreds of thousands on your own.
You don’t need to add anything. Enabled by default for some time.
5.15.y and 5.18.y for c, links for a and b are in description
https://www.armbian.com/rockpi4/
If some feature is missing, anyone can fix this for you … Its not Armbian problem, its your problem. Remember - open source, free software, …