Ha, I was just coming to post something similar. Hazy, milky summer skies in the 20th century were definitely due to pollution. Maybe there was occasional wildfire smoke but I don’t remember it. We have drastically improved air quality in the last 30 years, but now we get these smoky skies annually it seems. I know the last 3 years have been the worse for Canadian wildfires in modern history. I think there’s debate on how much wildfires are “normal” and what pre-colonization levels were.