the change in empathy has more to do with the change in social circumstances than it does a change in personality. This is part of what I mean by it magnifies who you really are. You see, when you’re poor you need the help of others- be it welfare, or more social assistance (parents watching kids, etc) you need that help.
So, you tend to give assistance with the expectation of social reciprocity.

It’s social reciprocity at play here… when you become rich, you don’t need to rely on it, so you don’t. Epitomy of “Got mine, fuck you”