You can't put a driver stack in a container. You can't put container stacks (c.f. Docker, Snap, Steam, Flatpak) in a container. Containers can't by default do oddball hardware access for oddball stuff like flashing firmware for your keyboard or 3D printer. You can't reflash your motherboard BIOS from a container.

The fact that your mental model of running your foreign Ubuntu software is "in containers" tells me you're probably mostly running backend/cloudy stuff. And yeah, that's largely a solved problem thanks to Docker (and for the same reason, "Dockerfile" is now a standard platform that everyone integrates and documents for by default).

Again, it's not like this can't be done from other distros, it's that it's fiddly and the instructions and defaults are all going to be for Ubuntu LTS.