Mary's stance is that she wants consumers to be enticed by the technology, rather than have it forced onto automakers. That sounds like an innocent enough motive however this could have far reaching effects depending on how that type of restructuring is carried out.
https://www.detroitnews.com/story/business/autos/mobility/2017/10/10/gms-barra-skeptical-electric-car-mandates/106499472/
https://www.detroitnews.com/story/business/autos/mobility/2017/10/10/gms-barra-skeptical-electric-car-mandates/106499472/