No it isn't. The heat coming from the computer is exactly the same per kWh as from a electric furnace.
For all practical purposes, you are of course correct. However, I seem to recall from highschool some decades ago reading about irreversible deformation and iirc, not all energy was transformed in to heat. I would assume the electromigration taking place in side our chips would fall under that. I suppose its like 0.0000000001% (if that) but just curious if thats correct nonetheless?