What exactly is missing from an iPad that would allow this to happen?
Some people have said ARM EL2, but virtualization in hardware isn't required if we can get a terminal with a jailed environment (akin to chroot) with brew. At worst you could spin up a Linux kernel in userspace if you needed to.
It forces emulation of x86. If only it could cut QEMU out of the equation it would be perfect.
I can't imagine it's still impossible for them to add similar functionality if it's the only thing holding it back from running macOS.
iPads work with standard mice, and have an on-screen mouse pointer. I used mine with an old mouse I had lying around a couple of weeks ago. Works fine.