Comment by mikepurvis

In the end they're probably run into the same issues that killed WSL1 for Microsoft— the Linux kernel has enormous surface area, and lots of pretty subtle behaviour, particularly around the stuff that is most critical for containers, like cgroups and user namespaces. There isn't an externally usable test suite that could be used to validate Microsoft's implementation of all these interfaces, because... well, why would there be?

Maintaining a working duplicate of the kernel-userspace interface is a monumental and thankless task, and especially hard to justify when the work has already been done many times over to implement the hardware-kernel interface, and there's literally Hyper-V already built into the OS.