Current iPads just don’t have the hardware support to make this possible. Hence why the DTK won’t support all the features mentioned in the keynote. (It’s using the iPad chip.)
They can make something work if Swift Playgrounds works (which is a pretty silly experience anyway. “Hey kid, great job learning Swift. Want to make a real app? Buy a $1200 MacBook and get to work!”
I’ve always found that strange given the demographic of HN. I’ve never considered good tools to be expensive. Continuous lost productivity is usually more costly than “Apple Tax”.
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.
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.
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.