CO2 was not claimed to be poisonous, at least not in the way implied.
CO2 increasing plant productivity only when there is a surplus of other resources. What I said about plants closing their stomata for longer still holds very true. I find it ironic that you’re supporting a conclusion gained from satellite telemetry. I would also like to point out the trillion tree campaign, which seeks to plant a trillion trees and is spearheaded by China, India, and Ethiopia.
During the Jurassic and especially the Triassic (Pangea), it is believed that there was a starker contrast between drier inland areas and wetter, river/lake/coastal areas. The prevalence of CO2 is an estimated average over millions of years. The criticism also ignores other factors, such as the sun increasing in intensity over time.
The forests aren’t the lungs of the Earth, but they are the carbon sequesters. As for the actual lungs of the Earth, they are facing habitat loss partly due to a tendency of lower productivity in areas with higher temperatures.
