The quite obvious answer for pax that can (due to their particular travel arrangements) avoid travel from/to/through any UK airport, and as crew myself, sometimes asked to position through the UK as a uniformed crew member, decline to do so, on a regular basis...as quite frankly the UK security staff have become so obtuse, I simply will not put up with it....nor will about twenty other crew members that I know of, who often travel on the same general schedule.
This also positively eliminates any travel on any UK airline...it's, hello CDG/FRA/AMS and AirFrance/Lufthansa/KLM.
Much better cabin service on the latter, anyway.