Aether contains the same flaw as Einstein's Spacetime. It forgets that there is an additional mechanical level that explains, for instance, the precession anomaly of Mercury.

When Einstein found his spacetime framework, he did not yet know about the Big Bang model. So, he left out the most important motion we all know today to be true. Matter is also moving in a single straight direction (away from where it all started), not-gravity based. Einstein did not incorporate it in his framework.

The real mistake Einstein made therefore was not looking for a mechanical explanation why Mercury has its precession the way it does, even after he learned about the Big Bang model.

So, he failed to see the fourth level (which is the First Motion, the most important speed we are all involved in).

Clever Einstein knew there had to be something, but he could not put his finger on it. Yet he was capable of intuiting correctly what the framework had to do.

Same for aether; it is a clever idea when realizing something is missing and no idea where to look.

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Earth, Sun, and Moon are moving through space like a car, a truck and a motorcycle on the freeway all going the same speed on the same stretch of freeway at the same time.

The truck does not do much circling at all, but the tandem of car and motorcycle are circling the truck, with the motorcycle circling the car as well. They all travel in the same speed, but car and motorcycle also circle additionally.

By not-recognizing all motions that matter is involved in, the precession anomaly of Mercury is explained by some folks as aether and other folks as Spacetime. In reality, it is explained by the First Motion of the materialization process. It is mechanical in essence.