People will live peacefully and happily in any system that offers them enough food, health care, a home, enough free time and so on.
This can be within capitalism but also within socialism.
You're right. It does not matter what economic system is for most people.
People want to live happily and peacefully. People want to be able to meet their needs. They want basic needs like education and health to be met. The economic system that allows them to provide is good.