That’s just untrue. Private for-profit prisons were a multi-billion-dollar industry for too long.
Also, they made enough money to bribe judges to sentence more people to longer terms so they could make more money.
Private prisons promised to be ‘more efficient’ and cost less per prisoner than public prisons, but typically their pattern of operations was to cut costs as much as possible and still charge the taxpayer more per prisoner than public prisons- and it got so out of hand that at one point it cost the taxpayer more per year to incarcerate a criminal than it would have to send him to Harvard for that year. Also under private prison administration, no effort was made at all to rehabilitate prisoners- their business was really based on recidivism, it was very much in their interest for prisoners to re-offend and end up back in prison.
Convict leasing on top of that is plain slavery, and the prospect of money to be made leasing convicts slaves for labor has corrupted America’s justice system, particularly in confederate states, ever since the 13th Amendment was penned.