C02 is important for plants, it's what they "breath".
But that being said as weather patterns change there will be corresponding shifts in the types of vegetation in various habitat zones. A desert getting a little more rainfall is not necessarily "good" from the human perspective. That rain has to come from somewhere else and likely that somewhere else is the smaller areas of land that are viable for farming.
The critical fact from a survival perspective that must be accepted is that human activity is altering the climate.
Definitely need to phase out hydro-carbons. But what alternatives are there that will sustain our current lifestyle?