If I was a tyrant, I would mandate everyone to daily exercise, only allow real unprocessed food for consumption while banning processed sugar and chemical additives, educate everyone on human history, human nature and psychology, maybe require a certain amount of time outdoors in the sun, create social bonds through physical games, etc. I haven’t thought this out but generally just make people do things that prime them physically and mentally, and let the experiment play out. Everyone would be free to go about their lives after fulfilling their daily requirements. Will this fix war, hunger, and general suffering? Absolutely not. It would be awkward if those things went away. But at least people would have some self respect and decency!