With a lot of luck and a bit of application the problem will go away.
There was no big splurge of attacks when the Met retreated to Lippitts Hill when their Enstrom 28 was attacked at Elstree thirty years ago, neither when the Merseyside AS355 [G-BOOV] was attacked at Liverpool a decade ago. Pilots landing damaged helicopters under fire in Rio - nothing new... just this time the bullet appears to have disabled the pilot [and potentially started a fire] with worse results than usual.
In recent years numerous helicopters have been under gun fire in the USA, and pilots wounded, but the numbers brought down catestophically have been nil...
Altitude seems a common factor in safety.
For the UK scene in particular 'Risk assessment' seems a good term to apply in this case.... now the warnings are there ... as yet no-one has attacked a machine tucked away securely within a building. It could be said that Google Earth poses a greater threat than Pprune.... two of the attacked machines feature there even if the images are a bit ancient. The start was a local argument in Surrey... the newspapers [not Pprune] appear to have done the rest as far as putting the germ of an idea in criminal heads.
That aside, blaming the media, pprune, Google Earth and everyone else in the vicinity may not actually tackle the short term problem.