I expect a lot of states will mirror the actions of the French, In the past the French state has paid the bills for calibration and operation of ILS systems at all the regional airports but this support has now ended. To replace these approaches the french govenment has introduced GNSS LPV approaches to replace the ILS. Some airports have kept the ILS at their own expense but others now only offer a GNSS precision approach with an NDB/DME as the last line of defence aganst GPS outage.
One only has to look just across the Channel to see the new order LeTouquet has now got GNSS LPV on both runways and maintains the ILS on one of these runways while Calais has withdrawn the ILS in favour of a GNSS LPV.
In the foreseeable future I can see only CAT2/3 runways having ILS with all CAT 1 runways going to GNSS, If the RAF wishes to maintain an airforce that has any credibility it will have to adapt to the changing aviation environment.