Einstein was able to arrive at all that because he submitted his own thinking to serious constraints. He never invented new things (multilapse theory worldpretation) but actually destroyed them.
What I don’t buy from his arguments though is that somehow gravitational waves would accelerate you. The universe is already accelerating, there is only the need for the waves to appear to main relativity. They don’t need to be the cause of acceleration, only if you assume the universe is not accelerating.
Of course there’s also the question of other reference points like looking at the stars and how they behave, but that would be too anti-dialectical for the last 300 years of philosophysical thought.
Centrifugal is running away from the center. Centripetal is the wrong name for it. It’s just the instantaneous tangent force.
Mach is wrong because physics only obeys instantaneous velocity. Changes in velocity produces/implies forces. Acceleration (rotation) causes all sorts of funk. Acceleration that isn’t a rotation could work alright.
The only way you could argue is in a perpendicular way to Einstein. It is true that were the center of rotation the Earth, then the Universe rotating around the Earth (Earth included by its own rotation), then if you were the only one not cosmically superglued to the Universe then it’s no different from you going for a run around the Earth.
EXCEPT… if the universe and Earth were rotating, you wouldn’t need to move your legs while the Earth slipped by right under you.