Is this thread an in-joke type thing? People are saying things that sound like memes so I'm not sure...
Or is it people who think evolution works like pokemon?
Or people who think that because gorillas and humans are both in the hominidae family we rely on one another?
We are quite a lot different to gorillas at this point, if their environment changes in a way that they can't handle they die out, we are great at making things though, and can even survive in extreme climates that would kill us quickly without specialised equipment. It depends what causes them to die out if you are thinking of how it will effect us.
If they die because the sun implodes, for example, we are pretty much screwed as well. But if they are killed off by a disease we may or may not be completely fine. You also have to keep in mind just how widespread humanity is compared to most other animals.