Bob Dylan was number 6 the last time they did this, at the very list this is a much better list than that one up and down the board.
I am cautious about a lot of this as it's subjective when it comes down to it, but I think that it's a bit unfair to those who are technically stronger because it's working on an assumption that they don't also get emotive or can't interpret the songs they sing in a fashion like that and I think a lot of them also have that down really well, including those way lower on the list or not on the list at all.
So, I went down a "Make You Feel My Love" wormhole as a result of this whole list because Dylan's high rankings on these lists for what, to me, is easily his worst musical quality, always flummox me. MYFML is later Dylan so the voice isn't anywhere near his 60s/70s peak here, and frankly to me sounds like a drunk man in his 60s in the local karaoke bar belting out an all time classic song. With that, I totally get how someone can really like that version of the song when comparing it to other versions. Joan Osborne's technically strong but really feels like it misses some of the longing I'd want from it. The Billy Joel version is rough in my view (I prefer the approach others took to the song). The Michael Buble version is...uh, Buble and really disconcerting to me (I had to stop it), Straight No Chaser makes some weird decisions, like, frankly I like barfly Bob Dylan's version a good chunk more vocally than most of them. Bryan Ferry's wasn't bad but missed a lot of the flourish that Dylan put into the song and the specific empahsises that elevate it for me (and Ferry is geat). Funny enough I feel like Garth got the emphases and pacing of the vocal and took it in a more hopeful direction - I like that one too, it's a very strong version of what Garth could do.
But the Adele version? Man, that's a vocal masterclass in my view. Not just the flat-out quality of the vocal but the decisions she makes using the tool to bring us through the journey of the song. I think it roughs out some of the harder edges on the original version while keeping a tinge of the sadness or even hoplessness especially at the end that Garth kind of abandons. It's intentional and it's beautiful and heartbreaking in a way that is a bit different than Dylan's version but no worse stylistically and several degrees better technically. Again, it's subjective and if someone doesn't like Adele I can definitely get that, but I think there's some objective elements to what a "good" vocal/voice/singer is just from what else is on the list and what people generally talk about with good vocalists, and in my view she does laps around many on this list on that. And I think it matters.
On the Celine note, I get Celine Dion not being on the list. I don't personally agree - she should've been there, but I get it ya know. You listen to a song like "It's All Coming Back To Me Now" and Celine belts the hell out of it, but I also feel like lesser vocalists who cover it get like 90% of the same things outta the song. Like even the Glee cover led by Lea Michele is functionally very similar. I might even prefer it a tinge. The late stage Meat Loaf version has the camp and charm I think as a vocal that brings something different and interesting to it. I'll totally nod when people get upset that a vocalist like Celine isn't there but I get it .
With that said, there should probably be more respect for those artists who can, in the words of The Weeknd, do what he can't do. I listen to Norah and Willie sing on the same track, as someone who loves both of them, and don't understand how the latter is #54 and the former is unlisted. Willie's singing can do a lot of things but, frankly, Norah's can do those same things but also has elements to it that are aesthetically more pleasing and skillful. You talk about modifying to the song, snag a listen to her versions of Here We Go Again with Ray Charles vs. Here We Go Again with Willie Nelson and how much she changes it up between when she has her own vocal on the Ray version and she's sharing with Willie - she modifies her voice to their voices. It's fascinating stuff. I've listened to both a ton, I've seen both live multiple times, I don't even think it's a contest as singers. Willie may be a better musician - songwriter, performer, etc. but singer? I can't get there. And I'm not necessarily arguing NORAH NEEDS TO BE TOP 50 or anything but I think the list, in an attempt to have a wide diversity of artists and with their odd voting methods, resulted in a list that rewarded a lot of things that aren't necessarily singing but artists who are representative of a segment of singing in a certain genre, style, or geographic region (or of greatness in the overall of what they do) that may not be the best examples of any of those as singers- which is how you get a list that says Jung Kook from BTS (who is a perfectly fine singer with no real solo vocal record beyond a couple features) at 191 and Celine Dion not on the list. Or you have Thom Yorke above Etta James - because while Thom Yorke singing "At Last" feels like it'd be riotously terrible...Etta James doing Paranoid Androiid likely doesn't work and they like Paranoid Android better than At Last.
. Plus when she really goes for it her pitch can go a skewed.