Well when the Sun turns into a red giant we’d better be interstellar. And the second point also seems to allude you, we are not like every other mammal, we are aware of what we are doing, have the knowledge of what effect we have on the environment, and can actually alter our behavior that makes a difference if we want to, unlike the rest of the animals who are basically oblivious and who btw seem naturally in tune with their environment unlike us. That is the burden of knowledge...
Then it seems humans could just as well be interstellar in 8 million years rather than being extinct. But wait, what really needs focused on is the suffocating big freeze.