Hmm, looks like someones trying to win an oscar in the "Best obtuse act" category.
People are in favor of states rights, as they are outlined in the constitution. Namely, the federal government only can extend its reach to the things the constitution states is under their umbrella, and beyond that is the states. However, the Constitution states which rights government, universally, can not touch....assembly, search and siezure, bare arms, etc. As such, being upset with a state trying to enact a law that potentially violates the 2nd amendment is not outside of the scope of "states' rights" but is actually directly in line with the philosophy as that philosophy is rooted within the constitution and from that same foundation we have the understanding that states should not be passing laws that violate the constitution, which those complaining about this generally feel.
Sorry, I hope I didn't ruin your oscar bid.