IMO...GM's problem is greed and being behind the curve on new car designs. Ford and Chrysler/Dodge have been putting out better looking cars for years. That's not to say no other manufacture will escape the same problems but my opinion is that GM has had the "old blood" in house that would wait to long for change and got out manuevered by the others.
The fella you speak of sounds pretty ignorant but I have always heard that ignorance is bliss!