The concept that seeking our own interests is to the betterment of the whole seems to be demonstrably false.. For example consider the tobacco and fossil fuel executives who are trying to delay the phase-out of their products. Or the people who buy/sell meat in spite of the resulting ecological damage & animal suffering.

By the way, a charity quite popular in mainstream Effective Altruism is Give Directly - which aims to avoid trying to figure out what poor people need by giving them cash.