Feynman actually did try to explain
Not in that particular interview which was very annoying. Feynman knew magnetism better than most people on the planet and instead of explaining it, he went off on the reporter for a badly phrased question.
He could have explained that magnetism and the electric field are the exact same thing seen from different reference frames. Instead he spent 5 minutes on why the reporter’s question was stupid.














Hubble proved it but it was also in Einstein’s equations. He thought his equations should balance so he added a fudge factor. That fudge factor was the experimentally proved Hubble Constant. Without the fudge factor, the universe expands.