Nobel Prize for Literature goes to Bob Dylan

I agree with this but this mostly also has to do with the nature of the music itself.  Many Johnny Cash songs are also like this (the difference being Cash has a much better, way more powerful voice). Yes, anybody who can hold a key can sing Dylan but it is also not possible to sing these songs any other way.  Jeff Buckley covered one Dylan track; horrendous, oversang it to death. I don't believe you could ask Dylan to suddenly stop singing gentle country-rock and perform Script for a Jester's Tear on stage but he wasn't even trying anyway.  Also, even John Lennon is only a little better that way.  Anybody can sing Imagine or for that matter most of the Lennon-rendered tracks on Beatles albums (at least Macca uses something that could be called range).  Lennon just gets away with it because his voice is more pleasant than Dylan.  There are plenty of celebrated but fairly mediocre/average singers in rock.   

 

To help you distinguish, listen to anything sung by Dave Cousins and compare it with Stevie Wonder and tell me who actually sings nasal.

I did say some people cannot give a free pass to Jon or Geddy and I'd hazard a guess that most prog fans who like Yes or Rush don't find their vocals distracting or annoying. In fact if you look at the majority of popular male singers they are singing in the upper tenor range which pitches them in the lower mezzo-soprano range of "lady" singers. Dylan is high baritone to low tenor without any real technique (this lack of technique is evident when you hear him speak) and all of it in the nasal voice or with nasal resonance. Stevie Wonder (a tenor) only enters the (nasal) head voice when hitting the higher notes in his range (which admittedly is most of the time) but at least he is capable of chest singing and can manage the transition between the two with ease. [I know people claim wide vocal ranges for many singers but I tend to regard them by where they are most comfortable and where they spend most of their time so while Dylan can go from C#2 to F5, the excursions are rare (and not strictly sung), as Madan says, it's mostly "monotonic"]

But, as I said, it's the aural aspect, the aural aspect of Jon's and Geddy's vocals fits the music as though it were simply another instrument, you cannot make that claim about Dylan even when he has a full backing band because the backing music is just a vehicle for his singing. Dylan is a singer-songwriter so should be compared against other singer-songwriters.