I'd guess that the inner parts of a forest environment, perhaps especially if wet (trapping dust on leaves) would have better air quality, but I'd expect that limited sunlight due to dust would be more of a problem than air quality. Smaller more generalist animals like birds and mammals understandably did better than large herbivores (and their predators) dependent on a single type of food source.
yeah thats probly right, inner parts of forest would be cleaner air wise dust gets trapped on leaves and stuff but sunlight is probly a bigger issue, less of it gets thru all the dust and thats bad for plants and animals alike, especially ones that need lots of it like big herbivores and their predators, theyd struggle to survive on limited sunlight and maybe even worse air quality than outer parts of forest, generalist animals like birds and small mammals would do ok tho, they can eat lots of diff things and dont need as much sunlight
