The problem with this theory is that Superman doesn't just spin the earth backwards, he then turns around and goes the other way to make it spin the right way again. You could say that maybe he messed up and went too far back, but he doesnt increase its speed to signify time going forward, it just goes back to its normal speed.
If you watch the scene
We see Superman flying fast around the planet. So fast that there is a light trail coming from where he had been. THEN the world slows down, stops, and reverses.
That light trail should mean he is travelling at the speed of light. According to scientists, time slows "DOWN" as you approach the speed of light.
So what happens if you travel faster than the speed of light? I guess you then go back in time. So, Superman must have been flying faster than the speed of light, and flew back in time.
Then what? At some point Superman would have to put on the brakes and slow down.
I believe that is what we saw. Superman reversed direction to slow down After all when was the last time we saw Superman fly feet first?
Superman was used to flying on Earth at only at a few 1000 MPH. It was probably easier to SLAM on the brakes hard to reach a specific point in time, then it would be to just gradually slow down, and hope that he happens to reach that specific point in time he was aiming for.
Once he slowed himself to a speed below the speed of light, the Earth began to spin forward again.
it was just poorly conveyed by the effects team.
That has to be what happened.
Remember Donner was not a scientist. He was a movie maker. Not everyone understands detailed scientific concepts
I'm going to ignore that and stick with the time travel theory.
It makes no sense to believe anything other than that.

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Maybe the image of the planet spinning backwards is only a metaphor
At the time the movie came out I didn't see it that way, but as time has gone on (if you'll forgive that expression!) I have come to.
"A big ball of wibbly wobbly, timey wimey stuff"
The Tenth Doctor explains all.

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Let's just call it ambiguous. Maybe the image of the planet spinning backwards is only a metaphor. Or maybe this movie takes place in a mythological universe like the epic of Gilgamesh, where the Earth is flat and held up by a giant turtle's back, while the sun and moon and stars are just little lights hanging from the canopy of the sky.

You nerds are adorable. Trying to make the case for logic in a science FICTION film.

You missed the point. The Earth didn't actually rotate in the opposite direction.

There are two problems which contradict your theory:

1. The Earth continues to rotate in the opposite direction even after Superman has completed his faster-than-light laps.
   2.Superman has to again to his faster-than-light laps in the opposite direction to get the earth to rotate back normally.
   If your theory was correct, then the moment Supes completed his first set of laps, the earth would continue rotating from West to East instead of the other way around. And he wouldn't have needed to fly a second set of laps to get the earth rotating in the right way again.
   You compared his motion to a clock. Again, if you turn back time on a clock, the minute and hour hands would be moving in the Anti-clockwise direction. But the moment you stop moving them, the hands again start moving in the clockwise direction. They would not continue ticking AC.
   Kind of like if you fast-rewind a VHS or DVD, the moment you stop, the movie continues forward not backward.
   "I'm the dude, playing a dude that's disguised as another dude".

Yeah, I knew this decades ago as well.
But then again, some people think the earth is flat.

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