On the flip side...
We could be Earth's life database only safety net.
If humans died off entirely, sure earth would thrive... But eventually something catastrophic will happen. Maybe not for a million years, maybe much sooner (like an asteroid). Humans, right now, are the only safe bet of getting biological information off the planet and elsewhere. Unless another species gets to our level of technology in however many million years, this might be the only shot for the species here to survive the planet itself.