You misunderstand the entire concept of Maxwell’s importance to modern civilization. Of course light and gamma rays are part of the electromagnetic spectrum - and they are also energy that could be available if we knew how to harness it - light is already partially harnessed by solar panels, but that is indirect.
Newton’s forte was a natural philosopher who laid the groundwork for the scientific revolution. Maxwell was a theoretical physicist who laid the mathematical groundwork for modern civilization - without whom Einstein would have remained a obscure mathematician working in the Patent Office and Tesla would have done something else.
You are so ignorant in terms of physics, optics, and electro optics....