Leica would disagree. Their Summicrons are pretty decent, and not very big. It all depends on how much the customer is willing to pay.
Good point. Would purchase a Summicron 50mm over an Otus any day ... if only they fit Nikons.
I suppose I should clarify: I don't think it's possible to create "world-class mini-
super-telephoto lenses" ... at least not yet.
I may be wrong in that regard though ... but haven't seen one yet.
I have two systems, a Nikon D3 and D-800 with several lenses including all three f2.8 zooms, and a couple of Panasonic GX8 bodies with a good selection of m4/3 lenses. When I went to Iraq as a reporter, I took a D3 with the zooms and a couple other lenses, and with all the other crap I had to carry like the armor, helmet & water, the weight damn near killed me. For the shots I took, I could easily replace that system with the GX8s and four or lenses that in total wouldn't probably weigh half as much...and for news purposes, the m4/3 is every bit at usable as the Nikons. (Actually the Nikon V system would have been even better than the Pannys, if it had a more complete selection of lenses...for news purposes.)
Interesting.
I don't see *any* advantages to a new APS-C system from Nikon -- I certainly wouldn't buy one. It doesn't have the weight advantages of the V system or the m4/3 systems, nor does it offer the quality of the FF or Fuji MF systems, so exactly what would be the point? A more interesting option from my point of view would be a Fuji-like MF mirrorless with a new lens mount that could also be used on a later FF offering...as a way to edge away from the F mount without really saying so, plus an upgraded V system with more lenses. The V is really a terrific little camera, and the 1-inch sensors are getting really good for what they are. They could cover selected pro work and virtually all news work, if they had a wider selection of lenses. And if Nikon really wanted to stay on top of the high-end, high-quality stuff, why not a sensor larger than FF? The Fuji, fully tricked out, is only a bit heavier than a D810, and with further miniaturization, I think Nikon could produce a MF body the same size as the 810.
My reason for being with Nikon is macro and telephoto. If I shot standard focal lengths (35mm-135), I agree there are many tempting brand options these days. But for sports/wildlife (extreme macro + extreme reach) the premium quality options are pretty much either Canon or Nikon, of which I prefer the latter.
In this capacity, the APS-C D500 is tough to beat. The most obvious advantage it has is
reach + speed + features. I recently sold mine, waiting for the D850 to come out, but after missing it for a month ... I re-ordered another. It is just too good, too fast, and too capable. Blows the D810 out of the water for action. Has better reach than the D5. Has better image quality than the D5 + the 1.4x TC to equal the D500's reach advantage. The D500 is IMO the most bang-for-the-buck, attractive wildlife camera I have seen.
I agree with you that MF will eventually shrink down to D810 size. At 46-50mpx, the D850 will, essentially, be a MF camera of 2 years ago.
However, thinking about that, this is another reason I went back to the D500. It is all I need for what I do.
Do I really want to riddle-off hundreds of 100MB images on my cards, and then process/save them, etc.? The D500 files are all anyone needs for magazines or internet presentation ... which is where 99.9% of bird photos, and wildlife photos, are going to be. Maybe if I want to blow-up some kind of incredible lion photo, to canvass a living room wall, then maybe shooting with the D810/D850 would be the choice. But for the most part internet/magazine articles are where wildlife photos go ... so the D500 is all the camera anyone needs for wildlife IMO.
Nikon should be announcing something this month, and I think the next year + early 2018 are going to reveal alot of cool offerings from multiple manufacturers.