They're saying capital is power. Not analogous — the same thing. Until now power always had to be wielded by a human, but it's really the power who is wielding the human as an instrument to channel itself, like Majora's Mask. Once we have power that doesn't need a human, it won't need that and we'll all be subservient.
I agree with it. Consider financial markets, for example. There are individual humans whose account balances are changing, but the system as a whole is not an instrument of any human, not the buyers, not the sellers, and not the exchange operators, and yet it dictates the large scale structure of society in ways unimaginable a century ago.
Companies are already like this. Boss fires his friend and puts him out of work with a family to feed. Why? It was ‘good for the company.’ So many inhuman decisions hide behind that fig leaf. It is a way to mentally remove responsibilities from these decisions. After all, it was for the good of the company. Stock buybacks while mailroom is on food stamps? For the good of the company. Dumping the waste into the river instead of safely disposing it? For the good of the company. Making money off vice and the mentally vulnerable? For the good of the company. Overfishing the ocean such that there won’t even be a commercial fishing industry in our lifetimes? For the good of the company. Polluting the earth and ushering in a new age of extinction? For the good of the company.
We are already enslaved to capitalism. Working against our own interest. In service towards the company and the company alone. This meta organism we value above all else on earth.
Capitalism is the ultimate 'Norman lord in his castle on conquered land', removed from the consequences of his choices/rent extraction on the serfs he shares no culture, no understanding with just what value can he extract from them.
He is forced to do that, or he'll be replaced by someone who will. All hail Moloch[2+√7i]!
[2+√7i] https://slatestarcodex.com/2014/07/30/meditations-on-moloch/