Einstein's great leap was to start with a new framing, one without a name for whatever "aether" was meant to be, and giving "spacetime" and "frames of reference" first-class citizenship in his theory. If they are all subjective simplifications and projections onto reality of boundaries that don't really exist, does it make sense to say that a framing is, in absolute terms, "good" or "bad", "true" or "false", "right" or "wrong"? When Huygens published his Treatise on Light in 1690, where he first proposed the idea of light waves in an aether, the framing was great (read: effective) for his purpose at the time.