Don't underestimate the corruptive influence of power and privilege either. I know it's unpopular to humanize the people who ruthlessly exploit others, but they aren't necessarily innately selfish, and are just as much a product of circumstance as others. The wealthy are perhaps the most alienated from the material and human cost of their wealth by a system that is designed to do so, and they are rewarded for behaving selfishly.

If you reduce the complexity of the world to "most people are good but the few bad people ruin it for everyone," then you run the risk of thinking that the solution to the problem is to remove the "bad people" from power and replace them with "good people." You'll inevitably be disappointed when the "good people" turn out to be "bad people" after experiencing power and privilege.