You might want to research
You might want to research the facts behind this story before coming to your coal fired conclusion.
Saabs brief CEO Victor Muller signed an agreement with GM regarding ownership change when he bought Saab in 2010. Muller tried to sell Saab in a way that would break the agreement. GM said no deal.
Why? Because GM already is a huge player in China, and didn't want to offend its existing partner there. By enforcing its existing agreements in both China and with Saab, GM clearly strengthened their already strong position in China.
Why didn't Ford care (as you asked)? Simple. They don't have much business in China, and no existing partner agreement in China that selling Volvo would harm.
They are very different situations, and if you get the facts about both you'll understand GM wanting to make Muller honor the deal he signed.
Saab will be missed, but it was not a sustainable business.