Or do they? At the bottom of the page, they list the parameters they look at. That list does not include "lens model" unless it is to be implied in the ellipsis . And if I had spent all that time and money gathering the data for all the lens models in the known universe, I would not have just implied that in that ellipsis
Of course, nor do we know that Nikon does that. We can only speculate that it is more doable for Nikon to do it's own lenses that they know so well.