Great images - However it was not an issue with the height of the bridge - the drone video and news reports clearly show that the vessel crashed into the pylon support which caused the bridge to collapse.
I agree - and not the sort of MO you expect from terrorists ( who target the maximum number of civilians with the least amount of resources not barely populated bridges in the middle of the night).
As I said above -even a malfunction in the steering/navigation- a huge cargo ship would take...