I agree, but I think the reason why we don't build pyramids today is because it would be a huge waste of resources. I guess you don't think much of Las Vegas-- me neither-- but the sphere is pretty darn impressive. There are all kinds of examples around the world with amazing architecture. The Hoover dam, the Golden Gate bridge, etc. If the Egyptians could have done these things they would probably not have built pyramids.

As an aside. When the Eifel Tower was built it was considered tacky by many and assumed to be temporary. Maybe some of the most remembered things of our time will be taken for granted. Maybe some huge data center will be a museum.