What manpower would be needed? How often are new aircraft validated? That's pretty scary that at the end of the day it's just a corporate shill pilot validating. What is the point of all the regulations if that's all that it takes?
Every single component in every single aircraft certificated in the USA is tracked all the way to the mine. A quick web search reveals around 11.3 million people work in the aviation industry directly. A significant portion of this would have to be duplicated if the FAA were to verify everything.