I'm a big States' Rights fan, so I think that this is a good thing, but we've sadly put ourselves into the position where it probably won't
matter, because the Federal government still has their "big stick" -- entitlements and Federal funds -- and states, localities and citizens have too
much attachment (and need) for those funds to give them up.
Need an example? When I was younger, the drinking age in Minnesota was 19. In 1984, that changed to 21, as it did for every state in the country
that had a lower drinking age. The federal government couldn't mandate it, because it would be a restraint of trade, so they passed a law (the
National Minimum Drinking Age Act of 1984) that said if a state didn't set the age limit to 21, they would lose some of their highway funding. South
Dakota challenged that, but in South Dakota v. Dole
the Supreme Court held that the Federal government withholding funding due to a state's non-compliance with a Federal mandate was legal.
The 1974 Federally mandated 55 MPH speed limit is another example -- the feds can't impose a speed limit, but they'll take away a state's funding
if they won't.
Assuming that this bill passes, and is upheld in the courts, I predict that the Federal government will react in a similar fashion to Arizona's claim
that they're not honouring some law, and then it will be up to the state to decide if they can afford to stick to their guns.