States may "have powers, not rights", but in common usage the theory is still referred to as "Sates' Rights." No unreconstructed rebel claims the "Recent Unpleasantness" was fought over states' powers, after all...
As for judicial challenges to the AWB of '94, how quickly they forget! See, for example, posts Tamara made @ The View From The Porch* about how, if you were able to talk to your 1995 self, younger you would not believe that 49 of 50 states had CCW, and most of them were "shall issue", that the SCOTUS had rules that the Second Amendment did apply to individual rights to keep and bear arms, and had been incorporated to apply to the states.
No such challenge was even contemplated.
*I'd link if I could figure out what to search for and find the posts/s.