Talk about safe guarding around established airfields who already have housing around them is going to be a spectacular own goal to GA airfields.
Realisatically to get the safe guarding back would mean the removal of several hundreds of millions worth of housing stock which there isn't enough of anyway.
It doesn't matter that the airfield was there first if the point is argued and the nimbys get hold of it that its unsafe having singles operating with out safe guarding you will be stuffed. The airfields will be deemed pref A airfields only and that will mean they will be shut for GA users. And then quite quickly afterwards be shut as uneconomic.