The old doctrine was that CO2 was a proxy for air quality, and the (somewhat overblown title) is about seeing CO2 additionally as having a causal effect.
For example, under the "proxy" model, if you're worried about infection risk it's sufficient to filter the air, but under the new model filtering will work less well than you'd expect because the viruses you miss will stay active longer.
"The old doctrine was that CO2 was a proxy for air quality"
That's not accurate, though. CO2 is, on its own, an air quality concern.
It has also been known, or at least part of the conversation, since Florence Nightingale's time, that fresh air reduces infections (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9300299/). This research makes a small tweak to our understanding, but it's also something that's been suspected/suggested by others for decades.
This research isn't "challenging" anything, it's merely expanding our understanding of causation about previously observed correlations. It's good to know what's happening. It's silly to make it out to be something it's not.
Listen. You don't get tenure confirming centuries-known ideas. You get it upending known doctrines. So if your research doesn't upend the doctrine, find a way to make your title say it does
For example, under the "proxy" model, if you're worried about infection risk it's sufficient to filter the air, but under the new model filtering will work less well than you'd expect because the viruses you miss will stay active longer.