I don't agree, Canon put their best sensor in the 5DIII, the fact that it was behind the competition is a different issue.
The requirements for non action photography did not evolve significantly between the time the 5D2 was released and the 5D3 was released. In other words the 5D3 was at least as good as the 5D2 for non action subjects. The fact that it could do more things thanks to a better AF, did not change its positioning as a body able, to some extend and to the best of Canon's abilities, to handle landscape.
Sony put its best AF system of the time into the A7r2. That makes it an action camera. At the time, the D4s and 1Dx existed
Nikon put its highest-resolution sensor into the D700. That makes it a landscape/studio camera. At the time, the 1Ds3 existed and the 5D2 and A900 were a few months away.
Of course not. Sony just didn't have an action camera in 2015. Canon didn't have a studio camera in 2012. Nikon didn't have one in 2018.
And the standard changed between the 5D2 and 5D3. The D800e was launched. The standard went from 24MP to 36MP. Otherwise so many non-action photographers wouldn't have abandoned Canon during that time. But they did - you can see it in the user-segmented market share.
I also don't agree that the D800's AF was poor. It was at least as good as the AF of the 5D3, using the same module as the D4, which Canon wasn't doing (the 5DIV is the first mid range Canon DSLR to use the same AF as their flagship).
Same module as the D4. That did not mean D4 performance. The D750 outshoots it AF-wise. Together with the 4fps frame rate, the D800 was not an action camera. The D850 is.
Staying at the same level as the D810 would put it equal to MF sensors. Are you saying that these aren't suitable for landscape work or that this is a compromise?
MF sensors of years ago. Times and standards change. 8 years ago, the 21MP 5D2 and 24MP D3x were the top tier of full-frame image quality. 21MP MF bodies were commonplace. These days, any full-frame body can outshoot them.
So, yes, it is a compromise. Sony and Canon put out 42MP and 50MP sensors two years ago. Any replacement will undoubtedly have higher resolution and (in the case of Canon) better DR. Both companies have demonstrated it. If Sony can build a 46MP, 9fps sensor for Nikon, it can build a 70MP, 5fps sensor for itself, for a no-holds-barred non-action body. The fact that Nikon went with that compromise - willingly or unwillingly - isn't a bad thing. It just means that this isn't the 5D2/D800e/A7r2 of 2017 - it's a general-purpose and action camera, not a resolution specialist.
I have used extensively my D810 with my 400mm f2.8 on various moving subjects and it is doing a great job, not as good as a D5 obviously, but great in absolute terms. Again, you are trying to present a biased version of reality to try to make reality fit in your model...
Again, this is just your view of things that isn't share by Nikon nor by a majority of the commentators reporting about the D850 announcement over the web. Seeing how you have to bend facts to fit into your mold, I don't believe that you have a correct view of things.
My view is that the D850 is a successor of the D810, but Nikon may release a new D5x or a D900 that expands their range towards even higher levels of resolution.
Who's bending facts now? You've gone on nothing but the name and said that the D850 is the direct successor to the D810, when the specs (relative to the standard of the day) don't support it, and even Nikon itself hasn't said that it is.
Take a camera with exactly the same specs and functions and put a D760 label on it. Now which camera's successor does it look like? What about a D900 label? Does it still look like a D810 successor?
The label doesn't make the camera. The features do.
