They've done that just fine for me by releasing... lame cars across the board. Most of their brands are shells of their former selves (especialllly Cadillac) and I can't remember the last time I saw a Chevy that I actually liked.
I mean, I get that. Part of it is irrational because my father worked for and retired from GM. So it's a bit of a family thing. But the loyalty has a limit and I believe Mary Barra has reached the limit for me.