You shouldn't repeat rumors you heard without any actual evidence at hand to back them up. That's just baseless gossip. It's poison spewing from your mouth to the ears of anyone who hears you.
I've also read convincing theories that he was on the spectrum, which could explain a lot of his challenges interacting with people, as well as his obsessive tendencies.
Empathizing with individuals is built into how the human brain works, because we can theoretically do something about the plight of a single person - at least, this was true in an age before mass communication, when our world was only as large as the people we interacted with. It was mutually beneficial for humans to develop an instinct to help those in their own social group, because it was more likely to result in one's own DNA being passed on.
Hearing about the problems of large numbers of people doesn't click the same way for us because, for the majority of human history, it didn't affect one's ability to further one's genes. Aiding some random person from a distant tribe just doesn't figure into an individual's reproductive fitness. We don't have an instinct to help people we don't know, especially when they don't have a name and a face. And so it's not ingrained in us. It has to be taught.
Lots of stuff needs to be done. Unfortunately, there is no political will to actually do any of it. Unfortunately, the unthinking ideology of a large enough portion of the population trumps the need to address the actual harm done to countless lives as a result of our inaction.
"Earth" literally just means "the dirt under your feet".
But most of us don't identify our location so broadly. We say what state or country we're in, and identify culturally that way. I imagine that won't change when there are people living on the Moon. They'll identify by the name of the base or settlement they live in.
Sprinkle in a little bit of "Loser" by Beck.