Mainstream economists turned climate warriors use cost-of-production methods to determine the “true” social cost of carbon. They appeal to a discredited methodology falsely attributed to medieval Scholastics.
It is easy to think of supply and demand curves as being key to economic analysis. In reality, they can't tell us much, and emphasizing them actually stands in the way of better understanding economic processes.
While economists and journalists are fond of saying inflation is "X" percent, in reality, the price indexes don't measure inflation accurately. Instead, they are statistical constructs created to benefit the government.