Vocal tone is the result of physiology, not talent.
Also, as I’ve mentioned many times on these boards, Geddy had mostly stopped with the “nails on chalkboard” shrieking by 1980, a mere six years into what has turned out to be a 37-year-and counting career.
Yeah, but he already did that sometime in the mid-70’s…anyway, that was a bit tweed-jackety of me, haha!
A combination of both, I’d say. You have the instrument you’re born with, but it takes work and taste to learn how to exploit it effectively.
Or perhaps review their perrennial struggle to be noticed right up til today. I say this as a fan.
I came in just to mention Sid Vicious, but the OP beat me to it.
To each his own, I suppose. I remember even when I was a big Metallica fan that I always felt like something was missing, but couldn’t quite put my finger on it. After not having listened to them for a number of years, I put on an album and realized how lacking the drumming was relative to the metal I had been listening to since. He may be an above average drummer, but I really feel like metal, particularly Thrash and other Thrash-influenced sub-genres like Black and Death really need a top-notch drummer.
That is, I feel like Ulrich does a fine job at keeping a beat, but he doesn’t go that extra step toward making the drum an integral part of the sound. I feel like his lackings were largely covered up by particularly catchy riffs. Whereas, I feel like each of the other members doesn’t just serve their niche in the band, but brought something more. For a sports analogy, I feel like he’s a serviceable quarterback who simply won’t lose the game for you relying on the exceptional skill of the rest of his teammates to win the game (eg, Trent Dilfer, 2000 Ravens) rather than the type that will is exceptional in his own right and raises the quality of play of all around him.
Moreso, IMO his performances don’t hold up well against many others in the genre, even his contemporaries. As I mentioned, I’ve heard plenty of modern bands perform Metallica covers and they usually embellish on the drumming considerably. Sure, a lot of that embellishment is nothing any more creative than adding double bass or blast beats, but I still feel like that’s a fairly significant difference in talent (eg, In Flames’ cover of Eye of the Beholder). I certainly can’t see him holding up to any modern Thrash drummer, even if the only real difference is speed.
Also, that story you gave is probably pretty close to what I read, I don’t seem to recall them later blaming it on the kit just on him. It was more of an aside anyway.
Hammett isn’t particularly impressive in terms of his speed, but I still believe he’s faster than most of his contemporaries. Beyond that, I feel as though he was particularly skilled in composing compelling solos. That is, as I mention above in seeing Lars as serviceable and not really bringing much more than keeping the beat, I would see a serviceable lead guitarist as the type who just knows his scales and plays them really fast.
It’s precisely that I think he brings that level of musicianship above and beyond and that so many of his solos really are timeless and make or break the songs is what makes him clearly a better musician in my eyes, and that I think that’s at least as important as technical skill, that’s why I’d put him up there for that era. There’s certainly far more impressive shredders out there, so “first class” might have been pushing it, particularly in light of how much of metal has gone toward the “play as fast and as heavy as you can” mentality. But despite that he probably couldn’t keep up in raw speed, I think that his solo-writing is enough to put him well above those, whereas I don’t think Ulrich brings that factor.
Like you said, to each his own. I’m not commenting about his speed–I couldn’t care less about that. I just find his solos neither compelling nor compositionally competent. ETA: I should add, I’m not a guitarist, so perhaps a guitarist’s perspective would be interesting. I just find his phrasing a bit odd, and his solos a bit disjointed and same-sounding.
Yeah, I kinda hate Hammett, but respect his technical skills, so don’t spend much time bashing him - besides if I want to point out a wanking shredder whose tech skills I respect, why unleash the fury on anyone by Yngwie? 
But yeah, I remember hearing the solo on Enter Sandman the first time - when he turns the one corner towards the end and does that wah-ish blues-ish lick a few times - it hit me like an ice-pick to the ear. Foul. But for the most part, his stuff tucks into Hetfield’s rhythms fine…
Mike Rutherford in Genesis.
Ginger Baker in Cream.
I find it more than slightly strange that Van Halen had its best successes with its least talented singers. They were successful under David Lee Roth, and again with Sammy Hagar. But Gary Cherone (while admittedly not the best fit for the band) was far and away the best pure singer.
Cherone is a fantastic singer, but his vocal style just didn’t mesh with the rest of the band. It was weird…it wasn’t Van Halen (or Van Hagar) anymore. And it wasn’t Extreme.
I have never rejected the Stones’ enduring popularity. 5 decades don’t lie. But I do reject the Stones themselves. “Satisfaction”, in particular, is lyrical nonsense. Musically I find them mostly unimpressive, but I could handle that were it not for Mick Jagger’s babbling on the microphone.
To me the Stones are nothing more than a blues/pop band that came over on the Beatles’ coattails and never evolved to any meaningful degree. I think they are the ultimate manifestation of style over substance. If you prefer, I’m simply not a fan in the same way that you’re not a fan of the Doors and I am.
Dennis was frequently happy to let Hal Blaine play the drums on Beach Boys records- partly because his studio technique was a bit sloppy and partly because working in the studio with a neurotic perfectionist like Brian Wilson was tiresome. Dennis could surf, drive his sports cars and chase girls all day, while Blaine made the records… and then Dennis could play the songs live, which was much more fun and paid a lot better.
And Dennis DID have great on-stage charisma. Blaine himself loved Dennis, and raved about the way Dennis could get thousands of girls screaming with just a little shake of his head. And that IS a talent!
Old joke:
Q: What does army coffee have in common with Ginger Baker?
A: They both suck without Cream.
There was a thread here a couple of years ago about The Edge’s sound. In that thread, Le Ministre de l’au-delà noted:
It does make it sound a bit like U2’s rhythm section is sometimes along for the ride. 
Before this thread devolves into being absolutely ridiculous, the criteria is “relatively untalented.” So being simply talented in a world-famous band with ubertalented bandmates doesn’t qualify you. Many of the folks mentioned here are fine musicians; they just play in bands with freakishly talented, one-in-a-million artists.
But there hasn’t been much discussion about current pop bands… which brings me to the Black Eyed Peas. Fergie and will.i.am appear to do most of the singing/rapping, and those other two guys… what do they do exactly?
Agree. As a drummer, I find it hard to believe anyone could call his contribution “weak”. If we’re doing Class of '77, I’d pt him in the top 3 along with Topper Headon and John Maher (of the Buzzcocks).
That bass on Sympathy For The Devil is played by Keith.
Not Bill. Well documented in print and film.
.
I remember shortly after Wyman announced his retirement, someone stuck a microphone in Jagger’s face and asked who he was gonna get to be the Stones’ new bass player. Chuckling wickedly and with a glint in his eye, he said, “Oh, I don’t know, maybe I’ll play bass. I mean, how hard could it be?”
Well stated - sorry for getting…passionate.
Andrew “Fletch” Fletcher from Depeche Mode. The joke amongst fans is that he provides “claps” because during the live shows all he does is clap along while standing at a keyboard. He is generally known as attending to more of the business side of things than the musical side.