I used to detest people who lived in bubbles, who lived only to serve the people immediate to them, and were ignorant of worldwide matters of great import.
But then I learned that these people are more pragmatic than I am, and strive to change the things that they are physically able to change, and let the fate of the world fall wherever it will.
On a global level, I see myself as a mere speck on one of the upper arms of the large expanding amorphously multitrophic organism known as "humanity". I cannot guide where it goes, or what it swallows, I can only tell the arm which direction to fall, and even then very seldom.
On a human level, we can directly touch and influence only a few people. The way I see it, why should I not just focus on these interactions and strengthen them, instead of distributing my finite energies weakly across an uncountable many?
I agree with you, and I think there's a degree of arrogance (or at least a lack of perspective) in pretending we have more influence than we actually do. It's better to do what we can than pretend to do what we can't.