Yeah, I mean, what kind of president signs such a law? Oh, wait...
The kind of president who gets political advice, ("Just sign this so you don't look like you're standing in the way of populist reform...") and is assured that the Supreme Court will get rid of it anyway, ("...and don't worry, the Court will declare this idiocy unconstitutional.").
Well, it took a few years but it turns out the advice was correct.