Haven't read the article (not loading), but with regards to the headline:
In a competitive market, this is precisely what we should expect. The price is driven toward the cost of production by competition. This doesn't include the externalities (it's not a part of the cost of production paid by the individual firms), so when you add them in the price is too low.
In a competitive market, this is precisely what we should expect. The price is driven toward the cost of production by competition. This doesn't include the externalities (it's not a part of the cost of production paid by the individual firms), so when you add them in the price is too low.