I have been using Nikon for over 40 years now and totally agree. They do make changes in all hardware that they do not necessarily talk about, unless it was publicized.
I have been told by NPS and NikonTech that they still do the same thing with their firmware updates. So, if it was a problem they discovered or a non highly publicized one, you can expect hidden updates.
I also know they tend not to update unless there is a bug after a couple of years, such as been with the D-70 and D-200.