that is such a stupid metric.
it's not like hiroshima was super hot for a day or two because the bomb went off, and the earth is enourmous compared to the city of hiroshima.
in trying to make a meaningless number (heat gained per second) into something people can understand, they just made another meaningless statement
350 nm is massive and ancient relative to new processes, but the name of a new process stopped physically meaning anything a while ago. for instance, the 3 nm process smallest distance between traces is only 24 nm.
now the industry just names a new process when enough techniques for improving performance (without much actual size difference) exist.