Didn't brand/model overload play a big role in the decline of US auto makers? I've heard this repeated many times but I don't know if it's true or not. Given th

Didn't brand/model overload play a big role in the decline of US auto makers? I've heard this repeated many times but I don't know if it's true or not. Given that almost all of the US automakers have drastically cut their brands/models over the last few years I tend to believe it's true.