I'm learning electrodynamics and one of the speakers I'm learning from said that when faced with the incompatibility of retaining both Newton's equations (based on mass, distance and time) and Maxwell's equations (based on charge, E and B) unchanged, Einstein had to choose one or the other. The speaker said that Einstein chose Maxwell's equations as definitive, meaning that he kept charge, E and B unchanged. Newton's equations became malleable, so that mass, length and time became malleable. I hope I'm not embellishing his point here. The speaker added that Einstein's choice was a reinforcement, at least for him, of the fundamental nature of the conversation of charge. In any event, I hadn't heard this perspective before, and was curious if those more familiar with electrodynamics and the roots of relativity could help explain why Maxwell's equations might hold preference over Newton's equations, or why charge, E and B would go unchanged while mass, time and distance are modified.