My close relatives have many genes in common with me. If I act on their behalf so that they live and breed my genes will be passed on even if I don't reproduce myself. The second type is called mutual benefit altruism - I'll scratch your back if you scratch mine. Both kinds of "altruism" have obvious benefits and it is not hard to see why they are selected for.However there is a third kind which is rarer. Some animals (principally primates) live in social groups which act together and have complex social lives within the group. In these animals group cohesion is important and there is selection for actions which preserve the integrity of the group as a whole. . .
I still don't see where your criticism applies.
No surprise there.
The last statement of the article (which is what I cited)says it all.