I think most of we more intelligent and perspicacious folk had assumed a medical event of some sort caused the incident.

Quite amusing though that some here professing automotive knowledge seemed to think the damage sustained in the collision was as a consequence of a high speed impact.

Modern vehicles are designed to crumple on impact and a collision with some unmoveable object at a speed between 20-30 mph will almost certainly result in destruction of the front end with serious deformation of the bonnet as the force is absorbed and routed away from the passenger compartment. The near side end of the windscreen is starred, not the driver’s side, and so it may well be the case the man slumped over sideways in that direction as he lost consciousness and his head hit the screen on impact.