The same model of jet that inspired the creation of the U.S. Navy's "Top Gun" program (and so popularized, by proxy, such memorable phrases as "kick the tires and light the fires") is now protecting North Korean skies, but it's the airborne equivalent of your grandfather's old Buick — the MiG-21.
Yes, the MiG 21 is no longer the scourge it used to be, especially in the hands of a North Korea (DPRK) wracked to strangulation with international sanctions.
Even Grandpa's Buick is probably in better order than the DPRK's fleet of approximately 150 or so MiG 21 flying jalopies — the country's most numerous fighter jet.