I strongly agree with you. I’m not against assisted suicide the same way I’m not against it for non incarcerated people. The only time I would agree with nonoptional state enforced death penalty is if the person is such a danger that they can either not be contained or are somehow able to continue to do direct harm despite all efforts of containment. This would be like trying to imprison evil Superman or professor X. Extremes only fiction has been able to create. This person wasn’t even close. I am wary of assisted suicide for the incarcerated only because consent isn’t a strong value for prison systems and could be faked/forcibly encouraged etc.
He may have been apolitical for his time (you’d have to ask him personally to know), but many teachings align with socialism. It just relies on the individual to do it themselves instead of being state enforced. “you do you but also heaven won’t accept you if you don’t share wealth”. Final judgement would stand in for corporeal laws in this case. When people don’t subscribe to that and it actively lets people suffer, teachings might not be enough.