Carbon Dioxide was chosen to be for the greenunists what "Goldstein" was to 1984.
A boogieman, an enemy that could be attacked again and again for "two minutes hate".
Alinsky's "Rule 13":
"Pick the target, freeze it, personalize it, and polarize it. Cut off the support network and isolate the target from sympathy."
How can "CO2" defend itself?
Unless one is well-versed in science or chemistry, who is going to argue FOR it?
It's become something of a McGuffin [a la Hitchcock] -- a useful diversion to win the hearts and minds of useful idiots...
Sadly, the STEM product of our higher education system is vastly outnumbered by over credentialed nitwits in other fields who pursued far less challenging courses of study, but whose relatively impressive CV suffixes (to some, anyway--a PhD who is wrong is just as wrong as a High School dropout who is wrong) tend to overshadow debate by bludgeoning those less credentialed with their letters of academic distinction.
But even more dangerous is the subsidized pursuit of ill formed conclusions over partial or doctored or even just cherry-picked data, bolstered by the conclusions of 'studies' preceding in a network of logical rabbit holes, unsupported by critical analysis of the hypotheses supposedly supported. Missing factors as simple as lower sulfide emissions or less insolation blockage from pollution reduction are ignored in the quest for a boogeyman that can be exploited in the public forum for prestige and profit. It is no wonder that succeeding studies will pursue that line of thought, especially if that pursuit is lucrative. For now, those who support such either are fully committed to the concepts out of error or misdirection, or seek to exploit those concepts for pecuniary gain, directly or indirectly, often through legislation which will have unintended consequences. If those (unintended consequences) manifest, then the concept and, indeed the system to which it applies, is not fully understood, otherwise, those consequences would have been understood as an effect of the action taken.
Which gets back to those claiming to be able to predict global temperatures decades, if not centuries, in advance, not being fully aware of all the interactions involved, natural or artificial, which means their predictions are flawed at best, or completely wrong at worst.
Naturally, if the consequences were understood and the action taken anyway, then we must assume that action to be malicious in nature, and not to benefit either the planet or humankind, despite a small group of individuals gaining power or profits as a result.