There is a famous said from Toyota:
No personality is our personality.
You don't like? I don't like so let buy it.
Family cars, as "main stream cars" as you said, for most cases
decision making is a result of compromise. Compromise among
family members, usage, reliability, performance, cost, utilizable
designs, safety, appearance, etc.
What is compromise? I believe that is "nothing". A good "nothing"
makes Camrys, Accords good cars. Again, a money making car must be
a good car.