From my understanding, a “national hit” is supposed to be the biggest hit out there in terms of charting and public recognition
The average number of weeks on melon of monster songs such as 2002, Through the night, Every Day Every Moment is about 100 weeks, which makes idol national hits digital performance not that impressive
Now let’s look at three massive songs that are currently still charting on Melon daily chart after more than a year:
#21 - Chang Beom June - Your Shampoo Scent in the Flowers (76 weeks)
#22 - AKMU - How can I love (71 weeks)
#14 - IU - Blueming (63 weeks)
As a reference, the common known national hits by girl groups don’t surpass the 70 week mark. Cheer Up leading with 68 weeks
So if we compare with non idol songs, there are actual national hits that idol groups can’t even touch in terms of digital performance
Overall, in my opinion, the only national hits from 3rd gen are Spring Day, Cheer Up, BWL (eventually) and most likely Dynamite too