But, they can be maintained. Changing the rubber gaskets every 100 years doesn't sound so bad. And glass will withstand water+wind forever, unlike stone. And it

But, they can be maintained. Changing the rubber gaskets every 100 years doesn't sound so bad. And glass will withstand water+wind forever, unlike stone. And it's easier to replace. And our steal&glass buildings might withstand earthquakes better. In the end, I think what matters most is "maintainability": if the interest/ value of the buildings exceeds the costs to maintain it, they can live basically forever - humans will make sure of it. Otherwise, they all degrade eventually.