It's wild to me that people make assertions like this. We can (and should) argue about the effectiveness of smoking restrictions on decreasing cancer and heart disease, but to make the argument that they have no effect is just silliness.
You hear the same arguments from the right whenever gun control, environmental protections or really any sort of government regulation comes up, and from the left (though to a much lesser degree) on the topic of tax rates. We should all be able to agree that any sort of regulation will have a marginal effect, and be able to have a discussion about the level of that effect.