Well, earth seem to pretty good in dealing with those mass extinctions, after all, we're already doing the 6th one ;)

I don't want to downplay the fact of how ruthless this teenage humankind is treating the world it's living in, but everything has it's place in the universe and I do believe that it will be a worthwhile lesson for future generations.

I doubt we'll be able to kill ourselves off entirely, we'll probably survive in misery and small numbers without the ability to cause anymore significant harm.

But I also think we as humans suffer from visions of grandeur, incredibly overestimating our own role and influence in things.