>You could argue that CO2 is bad.
CO2 is absolutely vital for plant growth. 0.04% is pretty much the lowest level recorded in historical sampling.
When CO2 levels are increased (0.08 - 0.12%) there would be a measurable increase in plant growth and planetary greening.
In commercial greenhouses CO2 levels are artificially increased to encourage plant growth.
The whole 'CO2 is bad' argument is just a ploy to destroy life and crops.