Large massive objects don't behave like small light objects.

Try balancing a toothpick on your finger. I find it impossible. Its very low mass, and therefore its very low inertia, gives it a very low resistance to falling over. Plus the distance it has to move to fall over is very small.

Try doing the same with a broomstick. It is easy to balance, though it is also easy to tip over. Unlike a large building the broomstick is built solid, and is proportionally very strong. The broomstick also has much less mass and is far shorter than a large building. The larger the object the more the tendency for it to maintain its verticle orientation. Plus the less solid, and less proportionally strong (like a building), an object the less likely it is to maintain its structural integrity as it falls.

A tall object must accelerate much faster to tip over, which requires a greater force. A tall object must move farther horizontally to tip over, which requires a greater force. A heavy object has more mass which requires more force to tip over.

A less solid, and less proportionally strong (like a building), object has less ability to apply horizontal force on itself when falling. An object that is already breaking apart has less ability to apply a horizontal force on itself when falling. But gravity is always present, and gravity pulls straight down. Gravity wins.

WTC7 did fall across the street causing great damage to adjacent buildings. So it wasn't straight down.