I invented VM live migration to solve the problems with traditional process migration, and my work was inspired by both Sprite and MOSIX. I believe that VM migration is in wide use today, especially at hyperscalers. Mike Nelson, who worked on Sprite, invented VM live migration in parallel with me, but secretly within VMware.

I feel like if you have a single system image, process migration is easy (or at least tractible), but without that, it's going to be pretty challenging. Live migration of VMs across hypervisors is more approachable than migrating a process between two individual systems... You've got all that I/O that needs to be proxied, etc.

Single system image across multiple nodes doesn't seem to be getting much mindshare either.