Its only for NFS and not NTFS and only in v4 of NFS at that. Most systems will not need any action and those that do are unique enough that they're should be patched regularly in the first place.
They’re probably also important and harder to support: things like central storage servers or other services which support a wide range of clients, careful security mapping rules, etc. This is less than a month old so I would not be surprised if the places affected are carefully testing since almost by definition anyone running it has a complicated environment to support.