That gives one basic ingredient that we need to live a meaningful life. I think another one is love.

I think there is something unnatural about the kind of “morality” needed for hunter-gatherers to live as farmers and city dwellers. The agricultural revolution came about too quickly for biological evolution to adjust. That adjustment had to be carried by culture instead. Organized religion developed to train H. sapiens how to live and function within large groups of strangers. This kind of morality (that requires extensive training and weekly reinforcement) is not found elsewhere in “nature”. Other species display varying degrees of (biological) altruism toward kin and tribe, but none to my knowledge turn the other cheek to strangers, and humans didn’t either, before the agricultural revolution and the invention of organized religion, both artificial behaviors as far as “nature” is concerned.

What we call a moral code has evolved - just like walking upright did - for the ability to survive. We learned to co-exist in a group for better survival. This meant protecting the weak and the young for better survival of the group. We are not the only specie to do this. These clans or tribes evolved into city-states and what we call civilization. Yet we continue to express the original traits of waring tribalism through ideological, religious, and racist persecution? We may not be as advanced as we claim to be.

I agree that supernatural belief and religion failed to harness immorality . But I suppose what really is unnatural is immorality not morality , if humans realize that
there's no rationality in immorality . Immorality is only the outcome of human egoism and sense of pleasure that's instinctual and not rational .

Yet there are examples galore of habitual criminals and miscreants who reformed themselves with the help of religion. Is there anything wrong with that?

People suck. They need to be told to suck less sadly. We're still animals and have those impulses. We made morality and I think has to be taught to fully understand and appreciate.