That's not what they mean by "rent-extraction". One of the problems with articles on Jacobin (which they try to combat but still fall short) is assuming too much prior context. It limits the mass appeal of their writing.
Those with capital are extracting rent for the use of their capital, much like a landlord with property charges rent for the use of the property. Rentiers (there's a term you can look up on Wikipedia for lots more) as a class are parasitical on actual producers. That's what's meant by the title - "the rent is too damn high". Not that the use of capital or property is worthless, but that the rent charged for its use is brutal and immoral.
Those with capital are extracting rent for the use of their capital, much like a landlord with property charges rent for the use of the property. Rentiers (there's a term you can look up on Wikipedia for lots more) as a class are parasitical on actual producers. That's what's meant by the title - "the rent is too damn high". Not that the use of capital or property is worthless, but that the rent charged for its use is brutal and immoral.