I mean the article mentions that GA (General Aviation) has pretty much adopted GNSS at this point. And its likely that airliners can afford the cost of INS as a

I mean the article mentions that GA (General Aviation) has pretty much adopted GNSS at this point. And its likely that airliners can afford the cost of INS as a backup system along with the other backup mechanisms mentioned in the article. "Today, however, navigation by global navigation satellite systems (GNSS) – backed up by ring laser gyro-stabilised INS/attitude and heading reference system platforms, radio beacons and air traffic control surveillance using multiple technologies – means that aviation has no real need to use a magnetic reference." Lastly, I would imagine the inclusion of AHRS systems as backup still supports a mission critical VFR/IFR type of flight. In the event of GPS jamming, I doubt non-critical operations would operate given the heightened risks.