Any correlation between gas stoves and asthma is likely because gas lines are generally in urban areas. It is too expensive to run underground gas lines to rural areas. Urban areas also have higher level of particulate pollution from vehicles, construction, and industry. The studies, if they show correlation, are the same as the studies that showed higher incidence of cancer near power lines. There is more cancer near power lines because there are more people near power lines.
You’re preaching to the converted. :-)
Not true. I grew up in a VERY rural area of south Louisiana. Gas transmission lines serving individual homes were run along highway/road rights of way in the 1960's. We converted our propane central furnace to run on natgas at that time.