Not having children is the single most biggest reason why people don’t give a fuck about life after they’ve died. They only care to maximise their individual fun for their lifetime. And what happens with the people that come after them, they couldn’t care less.
(Just to show how bland such general statements are.)
Empathy, self awareness and an awareness of all life and all the lives of others now, in the past and into the future is the single biggest reason why people give a fuck and are absolutely appalled at how so many people of every kind could be so aware of their collective destructive behaviors yet not want to do anything about it.