Theoretically it MIGHT (massively underline MIGHT) affect temperatures in much higher concentrations.
But let’s get serious. Pick 10,000 random molecules out of the air.
How many are CO2?
1000?
nope.
250?
nope.
100? Out of ten thousand?
nope.
50?
10?
nope.
nope.
out of ten thousand molecules THREE OR FOUR MIGHT BE CO2!!
So we’re gonna get boiled alive if all the sudden there were five or six? Out of TEN THOUSAND?
No way in creation does this make sense.
Oh, and as an aside, what type of organic molecule is the most prevalent on the planet?
A complex polysacharide, which is a fancy way of saying a type of sugar.
We call it CELLULOSE.
Cellulose is about 30% of the biomass on the planet.
Made by plants.
Out of sunshine and CO2
Everything is made out of Sunshine.