Chaos Jackal, as far as just artisticness is concerned, yes, I would say it is completely subjective. Classical songs are a lot more deep and complex, however deep and complex does not necessarily equate to "more artistic."
Look at John Phillip Sousa marches for example. All (yes, ALL, as in literally 100% of them) are written in the EXACT SAME FORMULA. Marches are written and played in sections, which go as follows: Intro, 1st strain (gets repeated), 2nd strain (doesn't get repeated), trio, dogfight, and finally, a repeat of the trio. Does this sound familiar? Intro (maybe), Verse, Chorus, 2nd Verse, Chorus, bridge, chorus ...?? Sousa follows a very formulaic pattern with his music, very similar to artists today, but I guarantee that there will be absolutely zero experts in music that would tell you that Sousa's marches were not artistic.
So I guess a tl;dr version of this would be that there is no "grade scale" if you will that we can grade a music's artisticness on, so it is completely subjective. That's one of the many reasons music is so interesting: every person, culture, country, etc. all have distinctly different kinds of music with distinctly different meanings, and what these people, cultures, and places define as "good" and "artistic" is completely different as well