It was almost certainly not supposed to argue against utilitarianism in general. It argues against the typical mind fallacy mostly; universal hedonic utilitarianism is just one particularly stupid incarnation of that, along with any other value system that arbitrarily values things valued by other minds without restraint.
This seems to be an argument against hedonistic utilitarianism, but not utilitarianism in general.
It was almost certainly not supposed to argue against utilitarianism in general. It argues against the typical mind fallacy mostly; universal hedonic utilitarianism is just one particularly stupid incarnation of that, along with any other value system that arbitrarily values things valued by other minds without restraint.
Also, the typical mind fallacy.