> I think the key may be to control it somehow.

How do you control something that per it's own definition works better the less controlled it is? Hence Le Guin suggesting that the inherent limitless uncontrolled growth goal in capitalism is akin to cancer. Because no cell is better at spreading than a cancer cell and when the body is consumed by cancer, some sort of equality is reached, that being every non cancer cell is equally influenced/wiped out by the cancer spread.

Theres short-term growth and long-term growth.

I think by good regulation you can get better long-term growth.

But that's just speculation. I don't know what the solution is.

Human nature corrupts every system, even systems that start out great.

So what you need ultimately is a system which can easily be shrugged off when it becomes corrupt.

With votes or dollars instead of bullets and blood.

Education maybe? It takes educated/ aware people to overcome tribalism and see that bettering societiy as a whole also betters them.

Capitalism can be controlled. Eg in China they permit capitalistic enterprises if it is deemed to "benefit the state or people". They also don't permit private enterprise to run the banking system.