You're right that it is the whole structure, but the whole structure is made of people, individuals. Collective action can't happen without individual action. You don't just magically go from no people doing something to everybody doing something. You start with one person doing something, then more, and more, and it spreads like a virus. Both good and bad behavior spread this way, not instantly.
Look, our literal job is to take hard problems and break them down into small and more manageable problems, right? Addressing the whole company is too big of a problem, you have to break it down. You, you are an addressable problem that you can change. The people close to you? Harder, but easier than those far away. They're also easier to convince when you make the change yourself.
Or you can just give up and rot in the soup. Would you rather try to remove the rot from the soup or bathe in it?
Processes, and the whole structure of company, and past events determines the outcome not individuals. And on top of that broad economic movements.
A good carrot in a rotten soup, is just a rotting carrot to be.