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.
Because it costs money. It’s not just “jobs”, it’s actual time and effort that we can’t spend on other things, which ultimately increases prices and means fewer people can afford things. And while in the West that means maybe cutting back a little, in other regions it can mean a life in poverty and premature death.