Before Oliver Heaviside, electricity was the province of scientists and inventors. After Heaviside, there was electrical engineering. He changed Maxwell's equations from twenty to the four we know, created the engineering mathmatics we spend semesters in college learning and defined the transmission line equations used in power distribution and printed circuit boards.
Heaviside's masterworks are free online at the internet archive. It's amazing how much he predicts the theory of relativity and yet could not accept it and said it must be some kind of joke. In that way, Einstein ended his career, because the scientific world he was mastering was suddenly gone.
In my book, anyone who can intuit something previously unknown, and then go about the difficult task of proving it with instruments of their own making, qualifies as some sort of genius.
But I agree that Maxwell did show that extra bit of insight, that tied together Gauss' Laws, Faraday's Law, and Ampere's Law, in one beautifully symmetric package. I laughed when our sophomore year physics book said that the symmetry of Maxwell's equations was "good for the soul." Honest, its very words. But there's something to that.
We all take these for granted now. Even, for instance, that recent discussion of transmission lines. These concepts are pervasive in everything we do.
Earlier when these hardware innovation were done, the scientist name got associated with those inventions but these days engineers who invent or write the app are hardly given individual credit. Its just the company's name.