I am saying that leaders who don't aggressively seek out the bad news first, and don't explicitly ask the same of those who they need to delegate their power to, are inviting failures like this. When the company in question sells products to which people entrust their lives, you bet I'm going to consider them more responsible than anyone else. They're more than happy to take most of the credit (as measured in dollars) when things are going well. They should be the first to accept responsibility when they fail, too.
On edit: The reason I am coming down so strongly on this side of the line is that, so far, GM has managed to fire 15 employees, none of whom served in the highest echelons of the company. When this is the narrative that is being pushed, it is crucial to place the primary blame where it belongs: at the top.