I would be fine with it if all prisoners had similar conditions, which they do not.

Also he and his supports have always criticized prisons for being "too luxurious", so hearing them complaining about his conditions now is infuriating.

As for rehabilitation, there is little hope for him. Prisons also serve to isolate individuals which are dangerous to the society, which he is (he is currently investigated for attempting to rig his current trial, something for which he was already condemned in the past).