You seem to be conflating capitalism with consumer goods.

Consumer goods may indeed disappear completely from the economy, though even this does not follow from your argument.

First: Capitalism doesn't require that corporate income is distributed through wages. The "capital" in "capitalism" implies owners, who can be paid dividends from that ownership.

Second: Before transistors, "computer" meant a human. Before AI, "agent" meant human. Specifically from the perspective of a firm, paying fees to maintain an AI agent isn't that different from paying wages to a human agent, and there are already plenty of firms whose business is selling to other businesses, "B2B" is the keyword.

Capialism also provides you free email and free ability to read and post here. Or do you think the Church or RedCross or Bernie is running HN? How did HN emerge out of capitalistic system? There are thousands of simple feedback loops interacting with each other to generate reality that itself changes from 1 day to the next. AI is like a weather system. Dynamical. Ever changing. Unpredictable. What human brains have always done when dealing with unpredictablity is to generate simple stories. In the past we used to call it religion.

Quick point on capitalism – the profit seeking motive is what makes the economy efficient and ultimately is what results in higher wages and living standards for everyone. We should be careful not to over-index on the direct effects of the "profit motive" such as profits to asset holders, while overlooking the far more important downstream benefits to society and workers. It's not win-lose.

But yes, it seems fairly obvious to me that if AI will effectively displaces all human economic value then the economy will not work for humans.

The only point I'll make on that is that I suspect you're worrying about the wrong thing. In a world where humans are economically worthless they're also politically powerless and entirely dependant on the decision making of the more intelligent artificial beings they've created. In this world your employment income will quickly become the least of your concerns.