Honestly it doesn't make a lot of sense. I'm sure we'll see a ZFC ii, which does make a lot of sense and will sell really well, and probably the Z30ii refresh which also makes sense.
But a higher performance DX camera? The Z6iii is that camera.
A high megapixel stacked sensor DX would be amazing for wildlife but what would the return on that investment be? I can't imagine the wildlife crowd is that large and how many would turn it down for the already existing full frame 45+ mp cameras. Wildlife shooters are one of the most demanding for image quality and spend big money to get every last drop of it they can. I just don't see how a DX camera, unless they spend big money on a stacked sensor 40+ megapixel version fits into that equation. Then how many 2500+ dollar DX cameras do you actually end up selling?
When the D500 was launched it made sense for the time. I don't think it does these days.
The Z50ii on its own merit is really a good camera for $900 dollars. A lot of people want it to me something much more for much less than the full frame options, like a budget Z8 I guess, but that doesn't make a ton of sense for Nikon to make if it cuts into Z6iii or other camera sales.
Under 1000 dollars though, what actually looks more attractive than the Z50ii right now? Paired up with something like a Tamron 150-500 and you have a honestly quite nice wildlife combo for @ 2000 dollars. Pair it with a used FTZ and older 150-600 Tamron or Sigma and you have a nice wildlife combo for probably $1500 or less.