I would say the big wigs have tried digital and didnt like its range/reception or something about it. Military is usually the first with new technology and its hard to believe they havent at least tried it out.
Range always takes a hit when digital is introduced at the same power levels. Unlike public safety, the military is usually using minimal power at max range in a mobile and changing environment for their comms. Digital functions well within a know area of good propogation or short range where there is little risk of enemy SIGINT interception or DF. Analog gives them the advantage of reduced power over greater range, and they do just fine for making it hard to listen to by using FHSS.
The article is about a very specific, very high-tech system that'd be revolutionary, not evolutionary, and people here come up with some BS simply focusing on the word digital, and then stating opinions & guesses about difficulties with digital comm systems.
Digital voice & data has been alive & well with military comms systems for a long time, despite the problems some of you have pontificated about here.
I spent about 16 years of 22 years in the military, using digital radio equipment almost exclusively. Digital radios opened up a whole new era for radio comms and what could be done with it. Like what a previous poster mentioned, this is for a specific system. Digital is alive and well in the military and will probably only get more complex over time. There has been purchases of multi-band equipment, capable of more digital modes, over the past 13 years, due to being at war. The last purchase I saw before retiring was to buy Thales and Harris software defined radios to replace Motorola XTS5000's.