The planet has dealt with some serious shit in the 4 billion years it’s been here… collisions with other bodies (one creating our moon), asteroid and comet strikes (as in the Late Heavy Bombardment), the Siberian Traps eruption, as well as other somewhat smaller events. Humans are just the latest cataclysm the world has had to endure.
As with all the others shit will get fucked up and the planet will heal itself long after we’re gone. We become so concerned with ‘Saving the Planet’ we don’t see the crap we do to ourselves and that 99% of our problems are self inflicted. The planet doesn’t need saving… we do.