I would believe that the aim of this resolution is to prevent the prison companies from making more money on more prisoners, removing the incentive for prison companies to promote/create a cause/turn a blind eye to crime.
Some services could be contracted out potentially to save costs. Of course, there’d be strict guidelines to ensure that these services are of a high enough quality. Though I am open to reasoning about why they shouldn’t be contracted out at all, and all run by the state.