You don’t have to become a celebrity that every random person on the street knows to try to do some good in the world, whether it works or not.
And objectively the internet is a safer place thanks to the Snowden NSA leaks which were directly inspired, not just ideologically but technically in how it was done, by Assange. You can look at the mass adoption of encrypted messaging and HTTPS adoption statistics (which grew exponentially directly after the leaks to become near standard), and plenty of other metrics to see that.
Wikileaks was the spawn of many good things, even despite it’s flaws.