It is true some modernist architecture hasn't aged well due to short-sighted deployment of the building materials and techniques available at the time. Frank Lloyd-Wright was particularly bad about this, and that could be attributed to the fact he was usually designing for ostentation. At the same time, there are modernist buildings demonstrating very intelligent choices over a the structure's long-term durability and maintainability. E.g. Bauhaus residences that put windows at the corners, to optimize on holes cut through exterior walls vs. natural light let in. Likewise for metal Lustron homes built during the 1940s in the US.