Back when he was starting out, Dylan’s voice was praised. That sort of rawness was considered important. Of course, nowadays people have been indoctrinated to only consider smooth, bland (but loud), perfect (with autotune) voices as good. Most complaints in this thread are because the singer does not have a slick, homogenized voice, that singers are required to have…
Most of the complaints here boil down to “the singer doesn’t sound like everyone else! How dare they have a unique voice!!!”
FIEND!
(There’s a, “Family Guy,” gag where a round-table discussion is being held with Kermit, Harold Ramis, Ray Romano and sportscaster Al Michaels. Très funny.)
John 
camp God I hate him. If I hear Jack and Diane one more time I might run amok in a shopping mall.
Thank you so much, Reality Chuck,for once again setting us all straight. 
For a while, I thought I had two: The Police and Sting. Then someone told me that Sting was the lead singer for The Police and it all made sense.
The Doors. It’s that organ sound.
Another vote for Van Morrison. Whiny and nasally.
Bob Dylan
UB40, particularly Red Red Whine (not a typo)
A more modern singer is Post Malone…or Post MaDrone. I hate his singing style.
Put me down for Neil Young. Oh my sainted mother. He sounds like he’s trying to sing through his nose.
[Slight hijack]
I’ve been trying to perfect my Christopher Walken impression for years. Somebody finally clued me in: Take Ray Romano and subtract Kermit the Frog.
[/hijack]
Adele often sounds flat (yo, that was real pitchy dawg) and has some vocal fry and vowel affectations that make me cringe.
Train… everything about that guy. Nobody wants to hear about your untrimmed chest there, chief.
Not sure they warrant hate due to irrelevance but Creed and Nickelback really are and were the worst.
I second Neil Young, because of his whiny, wind-baggy sinuses.
Tripler
Never cared for him, never will.
The oiliness of that guy oozes through my radio speakers. His songs are like stale cigarettes, beer breath and Joop cologne.
Fall Out Boy - yes.Totally. Adele - kinda hear what you mean about flat, and probably relates to my special hatred - everyone else - I don’t hear it - I don’t even mind Geddy Lee. Love Zevon btw.
Mine is Florence and her Machine. Don’t know how popular they are outside the Uk but you cannot shop here without being assailed by her noise. Holy Cricket (by which i mean i love nothing more than the game of cricket - so, trying to be sincere here) - she instills an armjerk in me! Straight for the button - any button! The sound is like a goose lost in the fog! Unfortunately in a shop, one is forced to abandon ones shopping or suffer the aural assault. I leave the trolley.
Ych a fi!
However, I am sure she is a lovely person who makes the best art she can - but for some reason that does not belong to her - it fries my ears.
MiM
Lewis Capaldi - its just awful ersatz emotion
Adele - to be honest she seems to be the model voice tone for Lewis Capaldi so it makes sense not to enjoy her stuff
Michael Stipe - He might be a wonderful human being, but his voice is the epitome of a miserable whinging whiny git
Joe Cocker - when certain of his songs come on I reach for the off switch - silence is far better
Janice Joplin - seemed to think that over effort = soul, no it does not, it just sounds like you are shi**ing your pants
Kim Carnes. Inevitably, during any discussion about '80s music, someone will mention her “sexy” voice. I don’t get it… Her voice sounds raspy and painful to me.
It used to be John Fogerty, now I don’t mind him so much. Never could handle Tracy Chapman.
Bruce Springsteen. Dude, unclench your everything.
Neil Young.
Tom Petty.
Lana Del Ray.
Cher.
Country singers with super twangs. See: Conway Twitty, Luke Bryan, and that dude that pimps out veteran’s charities.
Auggh, forgot the most annoying one: James Taylor! Often have I risked a broken finger, ramming at radio buttons to make that sound go away.
Annnd undoubtedly the vocoder effects on Life After Love utterly endeared her to you forever.
Passenger: I remember reading a comment comparing this guy’s singing to a Muppet’s voice after after it had been punched in the throat. I can’t disagree.