Thank you for posting this. I’ve been worried about this as well. In my long term study of humanity/Earth interaction and how to “solve” the problems facing us, I learned that the quality that allowed humanity to proliferate as we have and to survive the harsher climate our ancestors were subject to for most of our species history is neither opposable thumbs nor simply big brains but “altruism”.
We survived as a species precisely because of our ability to work together for the good of all rather than focus on defending what one family has.
Selfishness is only possible in safe and easy environments. When the going gets tough the selfish get extinct.