You're right about our leaders but partially wrong about it being too late. There will be massive destruction and horrible outcomes but damage can still be decreased. With massive effort fewer dead, fewer impovrished, easier to reverse. This is true at each point.

Horrifyingly though our leaders will do nothing while pretending when it gets bad there was nothing they could have done at this point. That it's always been futile.

You may think me saying humanity can still do good work to lower damage is optimism but as a pessimist I understand that nothing will likely be done. Especially when most think it's already too late to do anything.