That there were more stones moved in ancient times has no bearing on the fact that a larger stone (the largest ever moved) was moved in Russia in an age before heavy machinery, where it was possible for something like 400 men to drag and place a stone larger than Baalbek. The shape isn't so much the issue as sheer mass....yet we know it was done without alien help.
Yours is the argument from incredulity, the god of the gaps; 'how could the ancients have done it, therefore it must be aliens.' It's the same with 'God' - ''how could the universe come about on its own, therefore it must the work of God.'
