Uh, no, not even close. The 3rd party AF lens market for Z mount is thriving, although Samyang is not participating which limits it some, while in Canon RF land, only a few authorized lenses exist, and they're all APS-C.
My gut feeling is that Viltrox got Nikon aggroed by the release of the teleconverter that contains not just the "male" lens-side mount, but also the "female" camera-like one. Remember Sony doesn't allow third party TCs for E-mount ostensibly for the same reason: it licenses the lens-side mount, not the camera-side one, or we could have seen third-party E-mount cameras before long.
Of course I have no hard data on that, not even inside scoops (why would I?), but that seems to be the only difference between what Viltrox is doing, and what the rest of the third-party manufacturers are. There's lots of Z-mount lenses from China by now, some quite high-end, but only Viltrox got the writ.
