Never fear, before it's all over, this issue of "preemption" will be a giant game of "Whack-A-Mole". Knock down one law and several others will pop up. Wouldn't it be nice if their was a "punch card" system for Mayors and their entourage of fools? One where every law that got struck down caused their "card to get punched". Three punches and your out of office. Would make them think twice before proposing, and strong-arming through, laws that are patently against State Law or even Unconstitutional.
These idiots know that he court system takes forever to resolve anything. The time it takes from passage to being struck down takes years. By then they have a new approach ready to go. As an example, how long did it take Chicago and Washington, D.C. to have "backup legislation" in place? Even a financial penalty on the Cities for such legislation would be nice to see except for the fact that it would fall on the wallets of the taxpayers. It might be an incentive for them to make better choices when they select their leaders, though.