This needs Freedom Protests in the street.
https://www.ncsl.org/research/elections-and-campaigns/felon-...
In my opinion, we should focus on overuse and abuse of solitary confinement, but elimination is not possible for some prisoners.
There's also a big difference between "ruling out it's use entirely", and having hundreds of thousands of people in it every day.
It is not treated as a last resort in the current US incarceration system.
What will you do with someone who has beaten the shit out of another inmate?
Being able to see sunlight and other people isn't a risk of violence.
One would need to alter both in order to resolve this. Given their interlocking/reinforcing nature, it seems infeasible without some kind of revolutionary change in US politics.