Ancient Egypt's "bumps along the road" were several periods of almost total anarchy and state disintegration that each lasted for many decades.
You're right that there's nothing comparable to the modern era: the modern era hasn't existed long enough to have collapses that total. I think you are not applying the same level of scrutiny to ancient societies as you are to modern ones.
> Egypt, even though it was still intact by the times of Socrates, has had a number of changes and shake-ups, rises, falls, attempts to change the ancient state religion, etc.
There were some dynastic changes and bumps along the road, absolutely, but my point is the overall shape of Egypt was remarkably stable even through the Persian conquest.
Nothing comparable to modernity.