I’m using xhyve as well, but I’m having trouble getting it to boot newer kernels. 4.4 era works, (16.04) but 18.04 and 20.04 have various failures. I note that docker is built on xhyve and doesn’t seem to have this issue. So it’s not fundamental, but the fix hasn’t made it back to thx mostly abandoned xhyve.
Ubuntu 18.04 (Linux 4.15) in xhyve works fine for me. I tried to get 20.04 set up a while ago but I gave up because its installer kept flaking out on me, something about the disk if I remember correctly.
I finally wound up with multi pass, but on the Mac it’s limited to ubuntu images, and I occasionally need to spin up arbitrary distros for testing things.