You can have impact personally. That’s why many people hesitate to join a group and actually do something - they don’t understand only if they are personally active they can matter. Not doing anything because a person feels like activity is not realistic makes people resigned and idle.

Edit: I do understand your feeling of needing to have an impact. It’s important to understand what kind of activity is worth devoting ones self to. I personally feel motivated to be active when I watch superhero movies, so I guess it can have different effects on different people. As always, things are not black and white.