He clearly states a price range of $30-50 and the entire argument is built on that the price won't go up. (Otherwise why sell at 36?) The much weaker argument

He clearly states a price range of $30-50 and the entire argument is built on that the price won't go up. (Otherwise why sell at 36?) The much weaker argument of "over decades oil will have less importance" doesn't seem to be his argument at all.