How many unrealistic probabilities have come to be discovered to be probable. I remember reading the Lorentz’ contraction was a joke. Until Einstein.
Although his (Lorentz) equations worked, and Einstein used them in his Relativity theories, or came up with them on his own (I doubt it), his (Lorentz) reasoning behind it was that the electron, which had then been a newly discovered particle, did the contracting, as opposed to length (actually space). ie, the electron shrunk.