>What is the alternative exactly

There's not supposed to be an alternative.

To fully function within the system you need to be a corporation your dang self.

That doesn't mean you have to be a capital corporation, you can go forward without any of Other Peoples' Money and therefore not be an actual capitalist yourself. Even if you make more money per invested dollar that alone does not make you a capitalist, regardless of how much true capitalists can admire the returns. Without capital you would be merely an entrepreneur, sometimes that's a better choice, sometimes not.

Beyond that you still need to function in a capitalist market either way, no matter what because that's what dominates.

Which could be overwhelming too, and the kind of thing that would make a promising alternative seem very attractive also :\

The system is so totally dominated that you can't enumerate anything that is not . . . corporate-controlled.