Maybe that's the answer. There just wasn't enough material for planet formation..........................
Thank you for not grammar-policing over the "plant" spelling. (Dumb keyboard)
The way I interpret it, there SHOULD be a planet where the Asteroid Belt is, but as you say, there's not enough debris left there to explain it being destroyed. That's where the question comes up as to whether the debris was leftovers from the creation of the Solar System or the destruction of an existing planet.
If it's from creation, then Bode's Law is incorrect. If it's from destruction, then where's the rest of the phantom planet?
At this point, I'm still buying into the theory that Earth used to be where the Belt is today, collided with something and was knocked into the current orbit. There's a lot of anomalies in the Pacific Ocean (one being a much thinner crust than in the Atlantic) to indicate Earth was gouged out (pieces became the Belt) and the oceans filled in the hole.
Maybe that explains plate tectonics - the Earth's skin slowly covering over the wound.
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