First of all CO2 is plant feed and the world is 14% greener today. But even if we were to say CO2 was purely bad that's missing the point.
Burning Fossile fuel isn't just producing CO2 it's also allowing us to create fertilizers that keep 3B people alive, it's allowing us to produce cement, steel and plastic all of them the foundation of modern civilisation. Many of us wouldn't be alive if it wasn't for that.
On top of that it's what allow us to have machine do heavy work instead of humans, freeing more people up to do other things than working in the fields, which among other things gave us the internet which we are currently using, or many types of medicine, hell you can can't even do wind and solar without using fossil fuels.
So if we want to start counting externalities lets do that. But let do it fairly and it should be pretty clear that the positive externalities far outweigh the negative ones, which is why it's 80% of our energy consumption to this day.