I don't think we humans were made to think like that. Almost everyone mostly wants to live their lives and has just enough mental energy to care about problems in front of them.
To add to that, for the huge numbers of people who wouldn't be able to ride out a $1,000 emergency without going into debt, who feel like they're not even the primary causal agents in their own lives, the prospect of being able to have any sort of impact on the whole planet is absurd, even if they do have the bandwidth to think about it. They don't have an experience of, "When I decide something should be different, I have the ability to do anything that could actually bring that difference about."