Thom Hogan rated Nikkors on criterion of peformance on the D800/D810, and now the D850 raises the bar a few notches for optical performance. But technique is no less important with these HR sensors
High resolution media doesn't turn a good lens into a Coke bottle bottom. If the lens was satisfactory for a D800 and a D810 it will be for a D850.
For best resolution one needs high contrast and the image projected should be 200% that of the sensor or film. If at all possible the projected image should be at least 150% of the sensor or film. If the projected image isn't sharper than the capture media then the potential of that media will not be realized.
I edited this paragraph. I hope it says what I intended when I first wrote it.With higher resolution media, better lenses, better technique, better light, better subject detail, etc. will allow greater cropping or larger printing or both.
We all probably pixel peep but there is more to life than this. There are reasons good, practical and not so practical for pixel peeping.
I'm glad to see standards rise. I'm not glad to be so poor.
Dave Hartman
For a sharp image lighting that reveals texture is extremely important. I remember photographs of bird shot under flat, overcast skies with the AF-S 200-500mm f/5.6E ED VR and concern regarding lens sharpness. If everything else was perfect the light defeated any impression of sharpness.