I think earthquakes are caused by the ground contracting as the Earth cools. Civil engineers know about this when they design concrete and steel bridges. They have to make gaps in the bridge to allow for the structure to expand/contract during the seasons and day/night cycle. If no gaps are made then cracking can occur in random places jeopardizing the structural integrity of the bridge. The Earth has cracks for exactly this reason, the structural integrity of the crust is not uniform, and it has no place specifically that can allow for the entire crust to contract on itself as the Earth cools (the mantle solidifying). Earthquakes are the surface effects that are a direct result of the Earth contracting near the cracks where the structural integrity of the crust is weakest.
None of this is mentioned in Ben's videos. All the focus it seems is on disaster, catastrophe and the Sun.