In short, we aren't on track to an apocalyptic extinction, and the new head is concerned that rhetoric that we are is making people apathetic and paralyzes them from making beneficial actions.
He makes it clear too that this doesn't mean things are perfectly fine. The world is becoming and will be more dangerous with respect to climate. We're going to still have serious problems to deal with. The problems just aren't insurmountable and extinction level.
No, this is a misunderstanding. Cargo ships are a major source of sulphur pollution, not carbon. Cargo ships use the cheapest fuel they can. Cheap fuel is rich in sulphur. They can do this because there are no emission regulations on the open sea. A commonly cited figure is that a single cargo ship releases more sulphur than all the cars in North America.
This figure is then misinterpreted by people who failed basic chemistry to mean that cargo ships are a major contributor to greenhouse gas emissions. In reality, the opposite is true; cargo ships are one of the most efficient ways to move stuff over large distances. Only electric trains are better, and only if the source of the electricity is not fossil.