It doesn't have anything to do with how "good" their music is... The magazine used the term "girly" to describe Kreuger in the caption to a photo which had been included.
Good point, although I'm not sure that's how the magazine meant it... I think they threw the term "girly" out there in more of a derragatory way, seeing as how the photo and caption was inserted to accompany their rank as the most regretable thing about music from the past year (as per the reader input). Don't ask me how calling one's hair "girly" is supposed to be bad in a magazine which caters to a style of music in which it is not uncomon for band members to have long hair, a presumable feminine trait.