There has, of course, been evidence from some other European countries about a different approach being much, much better in terms of recidivism and also in terms of human dignity for the actual prisoners:
https://www.brennancenter.org/our-work/analysis-opinion/how-some-european-prisons-are-based-dignity-instead-dehumanizationUnfortunately, the UK has largely failed to adopt these measures and continues to follow a more American approach to punishment.
Without very significant investment, we are unlikely to see the kind of change necessary for a transformation of this type to take place.
Also, the dear old internet with its growing table of bigoted drunkards in the corner would make the serious conversations needed about adopting such an approach ever more problematic.