I have quite happily hiked in the Brecon beacons with a 1:25 000 OS map and see little need for GPS there (except in a whiteout) - I have quite a good sense of direction I think.
I regularly cycle in that area (but call it by another name) with a GPS and have no need for a map.
On the other hand try going through the Brechfa Forest with a map and compass and see how much fun you have.
The only "landmarks" visible are trees and paths. The former are only marked on maps as areas and the latter are frequently rerouted and not as shown on the map.
I still heat my house using a wood fire, most of you have a more advanced technology making your life much easier, like gas or electricity. Does your lack of practice at having to go through the repetitive task of preparing a fire and clearing ashes all the time mean that you no longer know how to light a fire? Should you carry on lighting a real fire every day to keep your skills valid, even though you have a machine that saves you all that tedious work? and is clean and is rapid and doesnt require a large storage area for fuel.
I "acquired" a full set of 1:50,000 maps for the UK in the 1980s, there value at the time was around £1,000!
Compare that to the price of an electronic device that does it all for you.
I will agree with a previous comment about "needing" map reading skills in order to prepare your routes rather than be in the hands of the Routing Software's Wise Guidance. Yet when I did my navigation training (pre-GPS) there was a hierarchy of good navigation methods and top of that hierarchy was not map and compass but
local knowledge.
Modern routing like Cycle travel seems to be feeding from such local knowledge in a way that mapping does not.
On my recent French tour, I put myself in its hands and it did better than I could because I dont know how to judge which French roads would give the best riding (CycleTravel has access to traffic volume data which isnt on maps, doesnt it?) Also it is more up to date than any paper map.
I bet the same army manual now has GPS as second place under local knowledge. Though of course the army has to keep map and compass as we may one day fight somebody big enough to "turn the GPS off".