Well.. in regards to life on planet earth, there have already been 5 mass extinction events. Though scientists believe that those happened due to volcanic activity and extraterrestrial objects. In our current mass extinction event it is believed that humans are causing it because the ecosystems are no longer balanced. Species die out even faster than they used to.
So yes, we are a net negative for all living things :D
But I guess there will be at least another life cycle before the planet becomes desolate. Maybe that one will be better, because in my opinion (no research to back that up) the current one is already fckd beyond repair
So, maybe we are actually a net positive, because we are causing the end of all suffering on earth? Hmmmmm....
Animals, despite not having the same level of intelligence as us humans, also suffer from pain that helps them to survive. But I guess their drive to survive is so much stronger and it's kinda sad that those beings don't get to "fulfill their reason". It's sad (for me) because we are taking away something that they want and I know how that feels like. Like society taking away my peaceful CTB methods.
That means we are a net negative for everything that wants to live.
(P.s. I couldn't resist writing my conclusion to this topic and it turned out quite scientific.. most of the stuff I already heard about, but wasn't sure if it's fact-checked by actual scientists. In my quick google searches I could verify my claims, but still don't know if I got anything wrong... Feel free to correct me, I really want to avoid spreading false facts.)