I think all smaller airfields with or without helis in the South East are under threat , not from left wing lunacy but right wing avarice . As someone said houses are more valubale use for the land and what could be better for a new development than abig open space.
Redhill, Denham and Fairoaks are in areas with very very high property prices and Elstree and N Weald not far behind . I doubt they will all close but I wouldn't mind betting two out of five will be gone inside five years. Maybe even Blackbushe although thats a lot further from London
Assorted EASA etc regulations will just be manipulated/selectively interpreted to hasten the process to hasten the process