A misconception here is that we're directly competing with Tesla on all business fronts. That's not entirely true. GM wants to become an administrator of a hardware ecosystem which can include a GM EV or an EV made by somebody else. Most of GM Energy's home hardware will be compatible with 3rd parties.
Also: I recently learned that Ford, GM, and the rest of the industry all use the same plug for their EVs. The only odd one out is.. Tesla. Annoying that the industry pioneer would also be the one who bucks its standards.
Edit: spelling