To me the problem is not the ignition switch, but the system design that disables the air bag deployment if the switch is not in the engine 'ON' running detent. In another article I read on this issue, there are no DOT (department of transportation) system design standards, and each company designs their airbag systems with no regulatory over site. The idea being they are free to innovate.
I would expect a proper system that if there are occupants sitting in any seat protected by airbags, the system would be armed. Think of a parked car, that is off, but is hit by another vehicle. Why have such an expensive piece of equipment, only intended to protect occupants if the machine is moving. Yes there may be unintended deployment, and a few deaths from this (recall the baby in the front passenger seat issue).
What I have not seen is a report of the 13 deaths, of how many were not using the required seat belt restraint system, as this was required, and the airbag is a secondary system. How many of these vehicles were operating in excess road speeds, and the driver lost control, as many deaths were the result of impact with trees. And it was the rough ride and going airborne that caused the junk on the key chain to rotate the switch to the 'AUX' detent.
There are many problems with expecting airbags to deploy, as this is a single string system. There's only one power supply, and single string sensors, processors, and explosive deployment devices.
I think GM has been thrown under the bus, with lawmakers that don't understand you can't make a perfect safety system.
But the engineers (and I bet many layers of management), ignored the root cause of the failure to deploy the airbag. And I bet they also rationalized that the operator had some blame in putting the vehicle in an adverse safety situation.