My point is that he libertarian approach is non-sense.

You have a market failure: pollution creates negative externalities and are over-produced in a free market.

You use one common solution to market failures: create property rights that can be protected by litigation.

You now run into another economic problem: Coase's theorem only guarantees efficient outcomes if transaction costs are low. The cost of litigation to enforce injuries as diffuse as environmental injuries would be huge.

You also run into another problem: it's nearly impossible to track injury resulting from pollution to a source once it's out and mixed with all the other pollution.

The libertarian approach runs face first into the brick wall of the very economic theory it's based on.

The sensible solution, as Coase himself noted, is a regulatory apparatus to stop pollution before rights are violated. As a lawyer I'd love the litigation free-for-all that would arise in the libertarian scenario, but it's just an unworkable approach. The fact that it is repeated so much is a triumph of ideology over rationality.