Fifty Fifty might be yes. Their biggest title is undeniably Cupid, but SOS, When You Say My Name, Pookie, and Eeny Meeny Miny Moe are all better songs. Arguably Higher is worse, but I think they're pretty even.
i-dle is no. Queencard is their biggest song, but Senorita is their worst title.
Dreamcatcher is harder to say... Maison might be their biggest song by virtue of being the only one that won awards, but they're a very stable group in terms of the level of success they tended to stay at once they gained popularity. My Christmas Sweet Love is a worse song, but it's hard to count given it's a Christmas song... I need
@Pirioca to weigh in.