Of course you’re correct that people are humans rather than idealised givers. This distinction matters, and sometimes it matters a lot.
I think there’s an important disanalogy between making econs a principal object of study and making idealised givers a principal object of study, though. Most of economics is descriptive—it’s about understanding how the world works, and that includes understanding how the people in it work (positive economics). On the other hand much of the work around effective altruism is trying not to do describe how people do behave, but to give goals of behaviour to which people can aspire (this is really normative economics).
Of course you’re correct that people are humans rather than idealised givers. This distinction matters, and sometimes it matters a lot.
I think there’s an important disanalogy between making econs a principal object of study and making idealised givers a principal object of study, though. Most of economics is descriptive—it’s about understanding how the world works, and that includes understanding how the people in it work (positive economics). On the other hand much of the work around effective altruism is trying not to do describe how people do behave, but to give goals of behaviour to which people can aspire (this is really normative economics).