Why is it that new energy will inevitably revolutionize traditional energy?

From the macro point of view of new energy, pure electric drive is a new energy for automobiles, which is less polluting than fuel using traditional fossil energy; For the field of power generation, nuclear fusion is a new energy. Compared with the current nuclear fission, the nuclear reaction will not produce radioactive substances and will not pollute the nuclear environment. The raw materials for the reaction are readily available and sufficient. Many advantages will inevitably seize the share of traditional energy.