The core concept of capitalism is that capital works for you. It separates earning money from working. If you have enough starting capital, you don’t have to work at all, because you can hire people to work for you and you can even hire people to do the hiring for you. You can even abstract all that away by not hiring but instead investing, and you can even pay someone to do that for you.
If you have money in a capitalist society, you don’t need to work, and if you don’t have money, you can work all you want and you will still not become rich.
On the other hand, the American Dream says that if you just work hard enough, you will be successful, you will make it, you will become rich, no matter whether you have money and contacts or not.
These two ideas directly conflict each other.
When do we reach the point where we get to post-scarcity and that we no longer work for money, instead we just try to make society better as a whole for our common goal à la Star Trek?
We are already post scarcity. The resources simply aren’t distributed properly or are wasted because of profit seeking. We only get a moneyless society far after the revolution. (So probably not in our lifetime unfortunately)