Interesting video; like towards the end, he touches on the idea there really is no limit to what we can build; BUT, we hardly can handle the unknowns of the Earth. So while we can build them, how long they'll stand is another story entirely; forget about unseen consequences.

Also, I wonder about the lifespan of these super structures; unlike their ancient counterparts, our modern buildings on average are designed to last from 30 to 50 years maximum. Who would pay the back end cost for the demolition of such structures. Heck, I wonder how long the ROI would be on something that costs so much.