It's because of the way we live. The capitalist/consumerist lifestyle is not very sustaiable because it burns trough resources too quickly. We could absolutely reengineer our civilization to be more eco-centric but that would hurt the billionaires.

A decentralized network of aquaponics systems could provide everyone with food. Cod houses are free of toxic chemicals. Vehicles that use compressed air in place of gas exist. Food can be cooked with solar cookers. Mechanical computing is a thing. And PCB boards can be made out of clay.

*By destroy I mean to make it inhospitable for people as we know them, planet will be fine long after we are all gone.

What if theres a new humanlike species after we are gone? They would not have the same knowledge as we do and could recreate the same, if not even worse results (especially if they rediscover our nukes) We made so much social progress, we cant just give that up now.