I've asked this question a few times but haven't really gotten a satisfactory answer. There are a lot of what I might call "epic problems" out there. Malaria, homelessness, HIV, refugees, war, climate change, income inequality, gender inequality, hate crimes. I don't know anything about creating vaccines or cures for malaria or HIV. I don't have a degree in social work or behavior science. I don't have any experience…
Your impact on the world isn't just what you directly build or finance. But also the impulses and ripples you leave through your interactions with other people.
As a sofware developer, I hope to make enough to one day to not worry about providing for myself and family. So I can more directly contribute to solving the world's issues. But until then, I can continue to try to be a good person and individual economic contributor. Donate what I can (time, brain power and money) to good causes. And to spread knowledge and ideas that, if they reach enough people, can make big differences.