It would be more reassuring if Nikon would release a few updated F mount lenses and accessories. But, all I've seen in the past year or so are Z mount lenses and accessories.
I would be surprised if there were a D7. Pleasantly surprised, but surprised nonetheless.
It's unfortunate that all of the camera makers are having such a rough time. I'm sure that most of their decisions are totally driven by how they might be accepted by investors. They can't really afford to continue building low margin DSLR's and build a comprehensive mirrorless system at the same time. Something has to give.
One of my all time major gripes with Nikon... and indeed other camera makers as well, has been that there are or were simply too many cameras with very similar specs listed in their current catalogs. There was a time when you could buy brand new D3200, D3300 and D3400 cameras at the same time.... they were sitting right next to each other in the camera store. Unfortunately, this philosophy has carried over to the mirrorless segment. Now that the Z7II and Z6II are in the catalog, is there really any reason to continue building and selling Z6/7 cameras? Please don't tell me they have two years worth of Z7/Z6 cameras sitting in warehouses somewhere. If so, they're in worse shape than I thought.
But I ramble ...