In many (perhaps most?) cases the feeling and motivation people have is the intuitive desire to feel good about helping others in their society personally, which is in many ways different from "true altruism". And it makes some sense (from e.g. evolutionary psychology perspective) to consider that our innate desire to "do good" is closely related to building social ties and status, and by helping people close to us in various ways (kinship, common "tribe-in-the-wide-sense-of-that-word", previous relationship history, expected future interactions) as opposed to simply helping abstract people as much as you can. True altruism is the exception (IMHO) rather than the norm, it certainly exists in some cases, but most helping others and charity and doing good is driven by "ordinary goodwill" that includes a mix of other motivations.
And, of course, if someone's goal is not really altruism, then doing more effective altruism won't help them achieve their goals. If we ("abstract we") want to optimize effective altruism, then instead we should help optimize people's efforts witin the area where true altruism overlaps with their actual goals to "do good" (whatever they mean by "do good" since that likely isn't exactly the same thing as true altruism); since once we get to the proposals which are more altruistic but contrary to their true personal goals/values, people are just going to reject the whole thing (as most do).