GM doesn't want to make cars.

Their current generation electric platform is optimized for small SUVs (Equinox, Blazer, Lyriq, Optiq, even the Honda Prologue and Acura ZDX), and their bigger electric platform for big trucks and SUVs (Silverado, Hummer) isn't selling all that well, but is strategically important to them.

It's easy for them to leave cars behind, because they haven't made money selling cars in like 20 years.