Ahh this old chestnut, it's always the same tune with slightly different lyrics, not long ago people decried GPS as going to make a generation of Pilots that don't know how to read Maps, before that I'm sure it was probably the ILS will make a generation of Pilots that don't know how to land, the Jet Engine is far too complex compared to a good old fashioned piston, all these fancy instruments will take away a Pilots ability to feel the aircraft, blah blah blah.
There is definitely a lower level of basic navigation skills since GPS became widespread. Is that a problem? well obviously not now as GPS is everywhere some cockpits having the option of up to 10 devices with some form of GPS on them, from the regulatory approved to flight bags and the pilots phone. The funny part is that the Aus regulators seem to think it OK that the backup network of navaids are mostly NDBs, which if you've ever seen a newer IFR pilot attempt an ADF approach in IMC without GPS overlays or such will make you walk away from aviation. Hopefully nobody turns off the GPS network on a bad weather day...
As far as map reading I've been watching multiple pilots who fly with their map not even aligned to aircraft heading...