It's about how correctly applied those punishments are. Just because it has the death penalty and high incarceration rates doesn't mean that they're being used correctly. For instance, does a serial rapist or serial child molester get the death penalty? In other countries he would. Why do people who were convicted with 100% certainty get put on death row for very long periods of time? People like public shooters and so on. It's a flawed application of the system in the US.
It still has death sentences and the dubious record of an incarceration rate higher than any other country.