Considering plenty of mummies had horrible teeth, I doubt it.

The Egyptians didn't each much better than us - lots of breads.

I would assume OP means by "feedback" the constant ripping and tearing of meat and incessant chewing of highly fibrous plants and vegetables.

I do but also when I describe the environment in which we evolved I'm not talking about the last 10,000 years really, so not including mega civilizations like the Egyptians. I'm talking about the other 99% of our existence where you largely took food out of the ground and occasionally directly hunted wild animals. The idea is that your jaw/teeth expect chewing this kind of food and use that information to determine how your teeth should be correctly placed in your jaw as it is still growing. I don't have any specific references handy but I first read about the teeth thing in the excellent book: The Story of the Human Body: Evolution, Health, and Disease

Which doesn't mean highly processed foods, just not living like hunter gatherers.

Well, I haven't seen a source for the claim that teeth were better when we weren't eating soft food, but the Egyptians definitely ate soft food, so I would assume that the hypothesis doesn't apply to them.

Egyptians that could afford mummification were probably wealthy enough to eat foods like honey and other exotic sweet treats on a frequent basis.

Dr. Mike Mew discusses it often: https://youtu.be/bvQwrGbqYKg