Eh... I dunno about that. Sure, people definitely trash a lot of stuff and we've all seen what environmental damage looks like, but we create an enormous amount of stuff also. Art, music, buildings, models, ideas, inventions, medicines, and the list goes on. As time goes on, things go obsolete, but new things often take their place. Heck, we've also created entire virtual and fictional worlds for each other to discover and explore.

So yeah, I'd have to lean on the belief that humans definitely create more than they destroy.