You have to remember that hundreds and hundreds of people died building them and some of them took decades to build as well.
Modern man could easily do it, but to do it like the egyptians would project the same fatalities and years to do it.
And back when they were built they had great mathmaticians to work out the best/easiest ways to do it. It certainly was possible for dozens of men
pulling on ropes to move the stones.
They also had big big whips.

