One of the reasons, Yes. Others included RS200 going off into a crowd. (Portugal or Corsica - Cant remember off hand) And the death of a crew in a Lancia. 1986 ish. If you've ever seen some footage from those days. You'll see just how close the spectators are! Some madder ones even had a habit of trying to touch the cars as they came past. Many teams, recall finding fingers in grilles!

Current WRC cars are actually getting on for the same speeds as the old Grp B days. (And thats with a restrictor!) Mainly down to better transmissions and tyres. We're nearly at the stage where the car can survive a huge impact, but the occupants cant survive such massive deceleration forces placed on their bodies.