Not sure why it's such a weird assumption that humanity is generally self interested and treats those in their immediate group/area as more important than anyth

Not sure why it's such a weird assumption that humanity is generally self interested and treats those in their immediate group/area as more important than anything else. For many people, the issue is that they'll only do anything to change their lifestyle once the problem directly starts affecting them and the people they know. Those in some distant country affected by heatwaves and extreme temperatures? Sadly for many people, their response is basically "not my problem" (even if in practicality it at least partly is). Is that the status quo? Yes, but for many people, they kinda like the status quo, and don't want to change. They don't seem climate change as a huge emergency (and on some parts of the political spectrum outright consider it left wing propoganda or something from an illuminati style conspiracy) and the political systems of today are not well tailored to dealing with it. It's easy to talk about re-thinking the world, but how do you think humanity would do that? Why would humanity change their attitudes on these things after centuries of self interest and tribalism?