I think there’s a problem with the bombs, at least at low BRs, like 6.3.
In recent days, I’ve often had the chance to perfectly drop bombs from a Spitfire (500 lb) with a 1-second fuse, right on top of a tank (Sherman, Tiger, IS, T34). The result has been several times that when the bomb hits the tank (turret, hull, sidepods, it makes no difference), the result is a hit, not a pen, and the explosion destroys the tracks and machine gun. It’s as if the game only senses the kinetic energy; the resulting explosion only propagates outward without doing anything inside the tank. However, when the bomb is dropped close to the tank (even a few meters away), the explosion destroys the tank as usual.