Request: directory setgid support in Azure Files NFS

Question

I was quite surprised to find that the directly setgid bit is not honored with NFS shares. For those who may not be aware, setting the setgid bit on a directory causes new files or directories created within it to inherit the GID of the directory itself; and the setgid bit is inherited by new subdirectories, too. This is, not surprisingly, a helpful mechanism for ensuring permissions are preserved on shared directories.

A bit of reading suggests that the NFS standard is not clear on whether or not the setgid but should be honored. But to be frank this is the first NFS server implementation I have encountered that does not. That doesn't mean Azure's choice here is the minority view globally, but it definitely is for my corner of the world.

Is there a fundamental, low-level implementation reason why the setgid directory bit is not honored?