Indeed, Red Hat is sponsoring students at Boston University to investigate turning Linux itself into a unikernel, with myself, Larry Woodman and Ulrich Drepper mentoring them (see link [2] in posting above). You can already run some smaller programs this way, either in qemu or on baremetal.
It's clear that bigger players, such as Red Hat[2] are interested in the topic of unikernels, and that cloud providers are preparing for this future too [3].
[0]: https://github.com/linuxkit/linuxkit
[1]: https://github.com/hckuo/Lupine-Linux
[2]: https://dl.acm.org/doi/10.1145/3317550.3321445
[3]: https://firecracker-microvm.github.io