Agreed but this is a professional camera and it would make little sense to use it with lenses that aren't capable of realising it's potential. I've seen a comparison of images taken with my D810 and latest the 24-70 against the D850 with the exact same lens and, with that lens, the D850 produces an image that is quite clearly more detailed etc. Now that's an expensive lens as is, for example, the 70-200 FL but these are the level of lenses that the D850 needs to be used with to really excel. It's a pro camera and it's meant to be used with pro lenses. Perhaps it's analogous to having a high-end turntable and fitting a cheap cartridge.
If I had, say, a D750 and a collection of medium grade lenses I'd know that the D850 would make little sense in pure IQ terms as the lenses would hold it back. There are of course many functional advances that the D850 brings regardless of lens choice.