@foxx How does termux work better? Even if you have a rooted device, you still aren't using the familiar GNU/Linux stack. Termux is still an emulator, it modifies the syscalls, and you don't have access to every directory.
In UT you can do everything you would on a desktop Linux distro but it is more difficult, mainly due to relying on hardware abstraction.
The only solution to this is using an upstream kernel with complete driver support. This is however a much harder task than the already hard porting process. PostmarketOS does that, and that's why almost none of their devices work fully.
All manufacturers should mainline their device drivers but none do, instead they use ancient downstream (often bugged) kernels so they can release their product quicker (and cheaper).
There are exceptions such as the Pinephone(s), which have full mainline kernel support, and allow using devices such as camera in the same way as in a normal Linux device.
In my view, Ubuntu Touch does solve a problem. It is the closest you can currently get to a normal GNU/Linux system, while retaining the phone's intended functionality (telephony, camera, etc).