In our life as humans during our brief time on earth we really leave very little, if any, legacy. There is really not much of us left behind, not much to know that we were even here at all. As a human on earth, we are just a blink in time. Whatever we do, good or evil will come and go and have no effect on existence outside of a few years of our passing. Even those among us that have made a significant mark in human history, even that is nothing more than a blink and will be lost to the universe.
Like a water droplet in the Pacific or a grain of sand in the Sahara. For certain there were brilliant or powerful or prolific humans before the time of recorded history, but they are lost, they have no legacy, just as if they did not exist at all. Perhaps now that we have invented tools and techniques to capture and communicate our bits of existence, we will not be lost forever, something of us will remain, at least while humans continue to exist on this planet.