When this experiment was used to support SR( having no need for a medium of propagation and interaction) and the concept of an aether was dismissed, there was an overall assumption made by those prominent at the time that the aether must be rigid and at rest.
Now that we know through the implications of General Relativity that even our OWN medium (space-time) has curvature, is capable of expansion and contraction,interacts with light gravitionally, is it not been made slightly redundant to up hold this requirement of rigivity and stationary state for any medium hypothetical or physical?
I'm not trying to be rude i just need the point i dropped the ball in terms of having to expect these conditions of existence of something.

From memory, the "rigidity" of the aether was calculated using the known speed of propagation of light. The "lack of motion" was the result of not being able to measure any motion. -C2.

thanks for your circular arguement