True costs of large scale toxic tech never 'plummet', or even decrease. The pathological metric of 'market costs' or 'market price' is all that will go down. The full and ongoing costs to life on earth keep increasing, inversely to 'market' costs or prices. True costs may start out relatively small, but will skyrocket as production ramps up.

Our crippled and toxic excuse for "economics" doesn't count those costs. But that deadly bill will come due - is already coming due - whether we count it or not.