People can't pollute Earth if there are no people

See, what you just said is exactly what I don't like about that kind of ideology. Extreme environmentalism, nihilism, all of it just comes down to an anti-human stance that tries to justify its ideals by saying that the whole species is horrible, that our existence doesn't matter, and that "life finds a way". It's impossible to know what is true or false because the size and age of the universe completely dwarfs our own on Earth, but that doesn't mean we should downplay our own existence because of that.

It's true that Earth has endured worse than us. Extinction events, plagues, cosmic annihilation. But we only know of these things because of their legacy, their history. Would you say that the dinosaurs, whose existence was arguably more meaningless, left no legacy when we know so much about them through their fossilized remains? Do all the ancient civilizations that have fallen mean nothing to us because they're gone, even after leaving us the ruins and texts of their labors?