The only difference with this firmware, I think, that my D750 shows, are three dots where the three cities are on the map. I looked at the time zone before and after the update. If anything else changed I sure did not notice.
If that is all this update does then Nikon must really have no needed software fixes or enhancements.
Big waste of software engineer time.
Like some have said, I imagine they fixed some unreported but very real rarely seen problems.