Now, in a very obscure way, you might be right, but I suspect not. Maybe tautology, but please explain. In what way is INS not stand-alone?
As you ellipticaly allude, INS is independent of external inputs. However most modern aircraft don't use it's raw output, rather it is used to modify position accuracy for RNAV, as is GPS/GNSS information. With the withdrawal of so many ground based aids only GPS/GNSS can produce an RNAV position of sufficient accuracy to conduct what used to be known as precision approaches where ILS/MWLS are not available and approaches to 'precision' minima where non - precision aids have been withdrawn.
The long term loss of satellite signals would be serious. INS is insufficiently accurate.