I don't shoot landscape, but many a press photographer and photojournalist would favour a 16-35mm/70-200mm 2.8 combo, because they can capture more with one on each body whilst only giving up 50mm in between. No loss!
Sony and Canon offer such 15/16-35mm lenses, whilst Nikon does not.
As always, it comes down to picking a system that's aligned to your needs.
These days I think brand ethos enters into it too.
I see Canon and Sony aligning more with jobbing, wedding photographers, photojournalists and the like.
Not just in lenses, but also by offering smaller and lighter kit.
Wheres Nikon seem to be carving out a niche more aligned to landscape, BIF, sports photographers and the like.
Size and weight is increasingly going out of the window in Nikon land, both in bodies and often in lenses too.