Of course it's stupid. You suffocate in an atmosphere of pure oxygen too. You actually NEED a small amount of CO2 to make things work right.Let's do a simple experiment
Place a plastic bag over your head and wrap it tight
Then tell us if Carbon Dioxide is a pollutant
Moron.
Key words? "Work right". Is true for almost everything. Too much air in the fuel mixture? Won't work right. Too much lead in your system? Things don't work right. Too much salt will kill you as sure as too much arsenic.
You are so right. Too much or too little of damn near anything can screw things up.
Carbon dioxide is a "trace gas" composing less than 1% of the atmosphere. A little seems to go a long way. It has enormous effects at that tiny concentration
You wanna double it? Triple it maybe? Still be less than 2% of the atmosphere. You really think things would still "work right".
I hope you try it on your home planet first.