@JoP, please explain how you can have an aether theory without collisions. It is my understanding that aether theories exist in order to provide the medium through which light waves move and that is through collisions.
If what people call an “aether” theory does not transmit light through collisions, then it is not an aether theory. It is something else. Sound is to water as light is to aether.
I think the problems are two fold: 1) people are calling things “aether” theories that are not in fact aether theories. 2) People really believe that somehow aether can transmit light without collisions.