Huh? Why does this person think libertarians would believe secondhand smoke is a myth? They might argue against laws prohibiting smoking indoors, but it wouldn't be because they believe second hand smoking is a myth.
This piece is filled with non-sequiturs.
It's nonsense.
Oddly, about the only people who might be forced to endure it are family/children of smokers, specifically while passengers in a car where the parent smokes. And there's no law against this. If a business/property owner wants to choose to allow smoking in their establishment, then it's the customers (or potential customers) that have the choice of being there or not.
It really isn't the place of the government to nanny state this one. And, again, I don't like smoking but don't feel it should be outright illegal. Drinking 2L of soda is probably as dangerous as being exposed to second hand smoke, but that isn't illegal either. If you don't like it, walk away from it in favor of someplace/business/location where it isn't allowed by the property/business owner.