If by "old concept of navigation" you mean our old friend the Navigator, the last plane to use one was probably not even in a museum anymore!!
In the absence of such a master of the CRP-5 Whiz-Wheel, FMS is his substitute, and if used properly, generaly does a great job........although it occasionaly does fly you straight into a mountain (American 757, Cali, Colombia).
However, raw-data flying, although no longer primary navigation, is still necessary to back up FMS, even if dual FMS computers are installed.