New wings do not equal new aeroplane.
Sure new wings will buy you fatigue life and reduced inspection and maintenance costs.
Likely there is some new wiring and componentry that comes with the new wings but there is a myriad of electrical components that have been sitting in the aircraft since manufacture, just waiting to fail on pre-flight grounding you for hours if not days.
New wings on a 30+ year old airframe are a false economy from a getting the job done perspective.
The problem is you can quantify the longer fatigue life and monetary savings easily for new wings. You've got to dig a lot harder to see the real hidden cost of declining serviceability and increased maintenance due to ageing airframes (Well, the components in them).
New wings do not equal new aeroplane.