Ubuntu Touch (or any Linux distro for that matter) offers drastically more freedom than GrapheneOS or any other Android distribution. Some people care more about freedom than so called "security", and I don't know about you, but I'll take freedom any day.
How can you be free when you're not private or secure?
Grapheneos is fully open source and comes with 0 Google services.
>so called "security"
Grapheneos is widely recognized as one of the most secure operating systems.
Freedom to get a stroke from an incomplete toy OS?
Snark aside, desktop Linux userspace (or gnu Linux, call it how you want) is nowhere near production ready. And even for the more general point, giving out root willy-nilly is not more freedom. It's more like letting your child play on the 5th floor of a half-constructed building that's about to be exploded. Your kid can enjoy their time just as much in the safe forest trail.