NVMM started as a new hypervisor for NetBSD but soon switched to DragonflyBSD as the officially supported host.

illumos occupied a small market but the amount of competition between distros is very high.

For example, there are 3 hypervisors on illumos:

Legacy KVM on DilOS

Legacy Xen on DilOS

Bhyve on the rest

Adding NVMM then we will have four. The more choices, the better.