If one takes AGI/ASI timelines seriously, it seems possible that many people alive today on death row, if they manage to avoid being executed, could reap the benefits from life extension (or more sci-fi alternatives) in addition to perfect rehabilitation. Aligned ASI seems to solve most/all traditional justifications for punishment: rehabilitation (no poverty, no fetal alcohol syndrome, pharmacological cures for violent propensity, low IQ, poor impulse control etc.), isolation probably isn't necessary with enhanced monitoring/surveillance (itself somewhat dystopian). That leaves retribution, which is not solved, but never made such sense anyways to physical determinists and free will skeptics. Perhaps ASI will allow more people to see the futility of retribution. One problem is that all of this sounds nuts, and policy makers might not (yet) take any of it seriously, and prisoners are a low-leverage group. But prominent policy makers are increasingly taking account of things that sound crazy.
I am an appellate criminal defense lawyer in the South, and it seems quite likely that we will all be ashamed in 10-20 years that we allowed executions to continue.