To be clear, climate change does not make the world set on fire in any conceivable scenario.
Not the whole world, maybe, but it is almost certainly exacerbating the risk of devastating natural fires in numerous
parts of the world.
In practice, to say the world is going to burn is not made in the literal sense, but to point out that climate change poses a significant risk of economic damage, loss of food production and so on that has a high risk of inducing social and political disorder. For instance, significant damage to parts of the world will likely induce mass migration, and potentially war. A recent study said that by 2050 global GDP could be only 4/5ths of what it should have been absent of global warming. Potentially, global GDP may even end up shrinking more than natural economic growth can offset.
Anyone who thinks migration to Europe and North America is a problem and serious threat to our countries, just imagine what it will be like if that ramps up an order of magnitude because poorer parts of the world start falling apart at the seams. There will be nowhere immune