Exactly, I drive past this barrier every day...the problem is the left two lanes on 101 are carpool/EV lane so Tesla drivers just zoom down it...at this particular exit, the left carpool lane leads to an HOV flyover exit which puts you on 85. If you are not paying attention (ie on autopilot flying past traffic), you will end up on a completely different highway! I see people very frequently swerve out of the flyover lane back on to 101 very often, so my initial thought was that he tried to disengage too late to either get back on 101 or the catch the flyover (not clear which one).
Before this rumour spreads: the latest Tesla statement [1] is worded in a deliberately misleading fashion and the only thing we can tell from it is that his hands were according to the software not on the wheel for 6s before the impact.
>The driver had received several visual and one audible hands-on warning earlier in the drive and the driver’s hands were not detected on the wheel for six seconds prior to the collision