Android does not have the same security model as desktop Linux. I made a comment about this above (which you probably can’t see due to .world being defederated with who I replied to), but if you don’t want to go to my comment history, it’s summed up as three or so main issues.

Rooting breaks OTA updates since it modifies your partition hash, meaning rooted users tend to leave security holes open way too long. Android does not have a package manager for you to be able to update these issues individually.

Android does not expect users to have root access, so they do not even consider it in the design. Android sandboxes apps, and apps can only generally have permissions that you grant, with no direct access to the kernel. However, rooting adds an entirely new attack surface for which there are no protections whatsoever. Desktop Linux, on the other hand, does expect users to need root level access from time to time. That’s what sudo is for, but you should not confuse this with switching your user entirely to root and doing everything as root. There’s a reason that’s not recommended on Linux: it’s dangerous. The same thing applies to Android. On top of that, Linux has other tools and protections designed to make running as sudoer safer, and Android has none.

Finally, it breaks your ability to use proper verified boot. If your system partions silently get malware installed, there’s generally no way for a user with a rooted phone to notice. Verified boot protects against this, but because rooting (along with whatever else you’re running as root) changes your partition hashes, it will either stop booting or revert your changes.

If mobile Linux ever takes off, it will likely be very similar to desktop Linux and be designed with root in mind.