It would be interesting to see the same before and after with automatically enabled fans that exhaust outdoors (where I am it's a requirement that they exist, but people forget to turn them on), since they greatly reduce pollutants [1]. I don't see any mention of this was controlled, even though it could be considered the most important component of a natural gas oven. Something with a $10 BOM could be made. If it did help, making something like that available would be an economically viable way to help the public. My gas to electric conversion was $6k USD!
[1] https://www.sciencedirect.com/science/article/abs/pii/S03601...