I've had discussions with at least two friends about the relative importance of musicality and lyrics. Both said they cared more about lyrics than musicality in songs that they listened to. I took the opposite view and will attempt to explain why.
There is nothing else quite like music. It's the indefinable aesthetic quality it possesses that stirs the soul. Lyrics, while also soul-stirring, have ancestry in poetry and prose. Not to say that this cheapens the value of good lyrics. But scarcity is and always has been a measure of worth. Find me another art from that has the same effect as a great melody and I will admit the error of my ways. I don't think it's possible.
A song is a fusion of music and lyrics. Music exists as the foundation of the song, while the lyrics give it integrity. As a final point, let me note the throngs of successful songs that have great musicality and poor lyrics as compared to the number of those with great, meaningful lyrics, but uninspired music. Ultimately, we listen to songs for the music. It seems painfully obvious. and that's because it is! At least to me, anyways. If I want a great message, a carefully organized grouping of words that will pull at my heartstrings, I could find it in a good song, yes. I could also find it in a poem, an essay, a moving speech, a short story, etc. If I want a brilliant melody backed by a wonderful chord progression, you'll find me going back to the music.