Corona virus has done a better job, fewer planes flying, less NOx, fewer collisions between planes and building above 35000 feet. Support your local Corona Virus and reduce early deaths from overexposure to laughing it's a gas.!
No mention of the thrust produced by the jet's exhaust stream being lost to the pollution control devices. To me it's a glaring omission that indicates it was not considered.
How about speed with props vs. jets? If it takes 12 hrs. to cross the Atlantic vs. 6 hrs. that means the turbine will have to run twice as long (for example). How will that relate to emissions? It is an interesting idea nevertheless.