Interesting and out of the box choice, but I have to agree with the Nobel Committee bringing up the rich tradition of poetry being an oral (and aural) art from antiquity. We no longer listen to Homer and Sappho and hear Beowulf sung to us, but we still read them.
It's a choice that must have been helped along by the equally rich Swedish (or actually, Nordic) history of having a very blurred line between what is a song and what is a poem. From the Viking-era skalds, the poetic sagas like the Eddas, through post-Viking royal chroniclers who kept records of the early Swedish Kings in poetic form through the 11th to 13th centuries,Bellman in the 1700's (often set to music right through the current day), all the way to artists such as Cornelis Vreeswijk, more or less a contemporary of Dylan's, or Lars Winnberbäck producing bitter and barbed social commentary in poetry-masquerading-as-pop-song. Or from another tack, pop band Mando Diao having a monster summer hit in Sweden a couple of years ago by setting a poem by beloved Swedish Poet Gustav Fröding to music.
So yeah, a surprising and unexpected choice, but a very very Swedish one.
(I'd post videos for all the above, but they're all in Swedish. So have some Dylan instead :)
https://youtu.be/mYajHZ4QUVM (It's Alright Ma, I'm only Bleeding)