Because they built something too big for the foundation? I bet if you weaken those trusses between 5&7, gravity will handle the rest. >The final design for 7

Because they built something too big for the foundation? I bet if you weaken those trusses between 5&7, gravity will handle the rest. >The final design for 7 World Trade Center was for a much larger building than originally planned when the substation was built.[16]:xxxviii The structural design of 7 World Trade Center therefore included a system of gravity column transfer trusses and girders, located between floors 5 and 7, to transfer loads to the smaller foundation.[0] [0]https://en.wikipedia.org/wiki/7_World_Trade_Center https://en.wikipedia.org/wiki/7_World_Trade_Center