> one could write a program in Unikernel style, as well as have normal programs look more container-like.

Projects similar to this exist today with https://nanos.org/.

You can run any typical web app (without having to re-write it) in a POSIX compliant Unikernel on most major cloud providers and bare metal. Each service runs in its own Unikernel.

I had its creator on my podcast the other day at: https://runninginproduction.com/podcast/79-nanovms-let-you-r...