A lot of the early days failure of Maxwell was his notation was insane. As others notice below; Heaviside notation[1] made it a lot easier to follow and calculate things. Notation is underrated as increasing human power: I'm not sure General Relativity would have been possible without Christoffel notation. FWIIW fun stuff to read; Whittaker's theories of Aether and Electromagnetism gives the detailed history of all this. Cheap from Dover books. Mind blowing in how theoretical physics used to work.
[1] https://books.google.com/books?id=nRJbAAAAYAAJ&pg=PA109#v=on...