I mean, they hunted mammoths to extinction so, pretty fucking effective lol

I mean, we're here, which means someone must have killed a mammoth.

But really they didn't hunt them with rocks on sticks. They chased them toward a cliff with their friends waiting at the bottom to dispatch any that survived the fall. This is why there's no more mammoths.

They weren’t very good at living for eternity? And really, who would want to?

Tge mammoths are all dead too so they were effective.