I’m not sure how that makes sense. Fewer vehicles equals *more* smog? If there was smog I highly doubt it was due to the vehicles (wildfires?)...as the technology is vastly different than the 50’s & 60’s respective to emissions. Today, even under normal traffic loads, car emissions are very low - nowhere experiences the smog of the past (in the USA).
The last city I saw real smog was Beijing, China.
“The last city I saw real smog was Beijing, China.”
I was in Bangkok earlier this year. Rarely say the sun.