I get a sense from some of the replies, that the confusion still continues about the difference between polluting gases and non-polluting gases.
Densely populated areas tend to have much more pollution than remote areas, mainly due to the huge number of polluting vehicles. As a result of the economic slow down resulting from Covid-19 measures, the air in cities has become noticeably cleaner, especially in highly polluted countries such as India where in some places people for the first time can get a clear view of the near-by Himalayan mountains.
However, CO2 is a perfectly clear and odourless gas; not a pollutant at current levels.