GM only has themselves to blame; they handed the sedan market to the Japanese and the Koreans, and their infamous 3.6L that they use across the board in almost everything is nothing short of a disaster. As much as I adore their fullsize SUVs, and they are essentially their bread and butter for the categories they compete in, not everyone is out there to buy a Tahoe/Yukon/Suburban - especially considering cost. This is, essentially, a repeat of history going back to the 70s.
They also singlehandedly tarnished reputable model names forever, such as putting the Blazer name on what is essentially a front wheel drive, unibody POS. Same goes for the Trailblazer, and the Equinox never really had any appeal to begin with. I have no idea what the point of even having the Trax is, and the Traverse I wouldn't touch with a 10 foot pole with that 3.6L. As far as their other brands go, I personally cannot bear to see the GMC nameplate on models like the Terrain and Acadia either, but that is just my own opinion. When you market yourself as "Professional Grade", you should not have disposable vehicles like those in your lineup.