Maybe the filtered air could be passed directly into a mask to be worn by the rider, so they don't kill themselves riding through the smog in the first place?
It looks like a great technology, but I think you'd need an army of people riding these to make even the smallest impact on a city/region. And while every small impact is a good one, I think this technology could be utilised in a more efficient, more impactful way.
I love the concept though!