further, co2 isnt' an an air pollutant. it doesn't cause ozone, smog, bronchitis, heart disease or cancer.
But increased levels of CO2 actually found in (some relatively extreme) workplaces in the USA do have significant negative health effects! Occupational CO2 exposure limits have been set in the United States at 0.5% (5000 ppm) for an 8-hour period.[88] At this level of CO2, International Space Station crew experienced headaches, lethargy, mental slowness, emotional irritation, and sleep disruption.[89] Studies in animals at 0.5% CO2 have demonstrated kidney calcification and bone loss after 8 weeks of exposure.[90] Another study of humans exposed in 2.5 hour sessions demonstrated significant effects on cognitive abilities at concentrations as low as 0.1% (1000ppm) CO2 likely due to CO2 induced increases in cerebral blood flow.[91] [...] Higher CO2 concentrations are associated with occupant health, comfort and performance degradation. ASHRAE Standard 62.1â"2007 ventilation rates may result in indoor levels up to 2,100 ppm above ambient outdoor conditions. Thus if the outdoor ambient is 400 ppm, indoor concentrations may reach 2,500 ppm with ventilation rates that meet this industry consensus standard. Concentrations in poorly ventilated spaces can be found even higher than this (range of 3,000 or 4,000). Keep in mind that levels under 5,000 ppm can cause negative health effects; that's just the level at which our government says you have to do something about it.
It is highly relevant what CO2 levels are like in our cities, and the things you said are completely irrelevant to that fact.