@errorcodevortex Your attitude is the problem here, demanding that this small community bend to support your own personal desires. That is not at all what Linux, Open Source, nor most of the communities around them, are about.
Libertine is the supported (albeit still an experimental feature) method of creating a container for installing legacy applications, yes.
If you want an insecure classic Linux distribution on your phone, then Ubuntu Touch is not it, and it never would have been, especially if Canonical had continued developing it in the direction they were going with.
There are plenty of reasons why it can't be a "full linux distro" by your standards, despite your refusal to accept how Android phones are designed and built.
On the other hand, if you do want something that is more like a traditional PC, where things could theoretically work more like how you want, and still want to run UT, then you could look at buying a PinePhone or Librem 5, both of which are not Android based, and therefore much more flexible in how things can work; though using apt to install additional packages and upgrade the system will still not be actively supported, it will work more reliably on such a system where partitioning can be better controlled by us, rather than having to conform to Android designs.