The only problem with theories such as the one put forward by Robert M. Schoch, is that the various pyramids and pyramidal structures around the world were built at widely differing times. The ones in the Americas and Southeast Asia are very recent compared to the ones in Egypt.
I believe the pyramids at Caral, in Peru, have been recently dated older that the Egyptian pyramids.
The largest pyramid in the world is in (I believe) Mexico.
Seems that the second oldest pyramid is the Hellinkon in Greece dated to , 2720BC.
Professor Stephen Oppenheimer has similar views
Eden in the East
The Drowned Continent of Southeast Asia
Stephen Oppenheimer
"The biblical flood really did occur - at the end of the last Ice Age. The Flood drowned for ever the huge continetal shelf of Southeast Asia, and caused a population dispersal which fertilized the Neolithic cultures of China, India, Mesopotamia, Egypt and the eastern Mediterranean, thus creating the first civilizations. The Polynesians did not come from China but from the islands of Southeast Asia. The domestication of rice was not in China but in the Malay Peninsula, 9,000 years ago."