No, it is an ordinary claim, requiring ordinary evidence.
The Egyptians had no magic powers. They had population, surplus food, and regular human ingenuity. Anywhere that happens, civilization arises, like desert wildflowers after a rain. If the wildflowers don't bloom, that requires explanation.
You do understand that we need evidence for everything, right?
But bending over backward to try to discount the evidence we have because it must be not just regular, workaday evidence, but extraordinary evidence, is not science. It is, instead, hardscrabble turf defense, and nothing to brag about.
> Lack of lost civilizations, where they ought to have arisen, needs explanation.
Well, lost cultures as advanced as, say, the builders of the Egyptian pyramids, but significantly older, is still an extraordinary claim.
In fact, claims of any kind of civilization existing require some kind of proof - it makes no sense to say "the British isles can sustain a thriving civilization today, so we should assume that there was a civilization present there 100k years ago, unless we have some evidence to the contrary (or at least wonder why no civilization flourished there some at that time)".