Given that the Z50II gets pretty much all the goodness trickled down from the Z9 with EXPEED7, that changes the equation for any "higher end" DX cameras Nikon might make. The additional features that would be necessary for, say, a Z70 model, have all simplified down to:
- More megapixels. Competitors to a higher-than-Z50II are essentially the Canon R7 and Fujifilm X-H2S. Both those have more pixels. To compete with them, Nikon would need a new (and very fast) image sensor with more pixels.
- Faster read-out speed. The Z50II is going to bend hummingbird wings when using electronic shutter, so the top-end users are going to want a faster electronic shutter. That goes with the first bullet to combine as "new image sensor."
- Sensor stabilization. A slightly tricky bullet, as most of the lenses that the high-end APS-C customers are using tend to be telephoto (for birding, wildlife, sports), and Nikon has VR in its telephoto lens set. One might argue that Syncho VR type performance would give higher CIPA numbers, but frankly, we lived very happily in the two-axis VR world for quite some time. A fast mid-range zoom with VR would be necessary for any Z70+ camera, though.
- Faster/More cards. The Z50II has the old fixed 200-frame buffer limit, and it doesn't provide backup capabilities. Most higher end users would want unlimited buffer and two slots, which means CFe+SD in a smaller body.
That's pretty much it. Yes, I can think of plenty of other things that could be added/improved, but those four things would be the primary ones that a high-end APS-C (DX) customer would be looking for that the Z50II doesn't have. Without the above four bulleted items, a Z70/Z90 needn't exist.
Here's the problem: new image sensor R&D cost has to be returned via volume sales. Ditto Sensor VR in a smaller body, though that's probably not nearly as big an expense. Nevertheless, the question becomes whether the expected volume of such a camera could justify those expenses. Given the Z6III having all those things (though at a higher price point than a top DX would likely be), I'd say no.
I can imagine a lot of ways the DX lineup could have gone. Nikon seems to be sticking with their original plans here, and that doesn't seem to include a high-end model; they want to push users to FX for that. The fact that all three current models are based off the same image sensor and most of the same supporting technology—EXPEED7 needs to eventually make it to as many cameras as possible to lower its R&D cost per unit, so I see it coming to Z30II and ZfcII someday—seems to indicate that Nikon is trying to minimize DX R&D costs. That says "no new models, and likely no new image sensor until absolutely necessary."
That's now my prediction until something convinces me otherwise: the Z50II is the top-end of DX for the foreseeable future.
