Most of the comment is great, but

if you personally fulfilled even some modest dream of a large proportion of the people on earth, you would be wealthy beyond the dreams of lucre.

this part seems like a Just World Fallacy. You can start a chain of cause and effect that will make billions of people a bit happier, and yet someone else may take the reward.

But I agree that on average making a lot of people happy is a good way to get wealthy.