>>3432735The way I see it her popularity has more to do with her just having a knack for show biz and natural charisma rather than being that much cuter than the others. Though the realistic answer is that it's an anime so of course all the girls are cute, and the character designs are meant to be simplistic and similarly templated.
>it's almost unheard of for Idols to last more than a year or two before dropping into obscurity.Onpu's popularity level feels contradictory at times (1 million fan club members and such) but I always had the impression that she was kind of a B-list idol. Meaning less so that she was really that popular for years but rather that she was never that big to begin with. I feel like that makes more sense with her character arc as well. Maybe I'm overthinking it though.