Even dead, Jim Morrison has it over Robby Krieger.
Vastly bigger disparity between Jim and Ray. And between John and Ray.
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Except that Art Garfunkle does have a (deserved!) cult following, whereas Paul Simon’s been playing to a top 40 pop crowd for 30+ years. I’m not sure that’s cooler.
That’s a valid way of looking at it. But even if you think so, then the dichotomy still applies. The two men’s personalities are completely different; if you think one is cool, then the other isn’t.
It seems like there are two things going on here.
First, the lead singer of a band is, almost universally, more famous than everybody else in the band put together. But that does not seem to get at what the OP is asking about.
I think what the OP is asking about is, well situations like that described in the OP. Phil Collins had some cool songs but also a lot of incredibly crappy, vapid, annoying, play in the waiting room of the dentist office type music, while Peter Gabriel is still making incredibly cool, mind blowing music.
It seems to me he is asking about situations where you say, whoa, I can’t even imagine those guys in a band together. I guess it’s where the one person continues doing cool stuff, and the other person starts doing really crappy stuff.
I think a more interesting comparison is John and Paul. Like Collins and Gabriel they were both leaders of the group in terms of singing, songwriting and projecting the groups persona.
Paul is at least as popular as John, maybe more, but I think John easily wins on cool points. However, I don’t consider any of the Beatles lame.
Even though Townsend/Daltrey are the Who’s equivalent to Lennon/McCarthy and Gabriel/Collins. Keith Moon out-cools them all.
Okey doke – Mick is sexy (still, believe it or not), but Charlie is cool.
Yeah, I was thinking the same thing, and in fact came in here to post John and Paul.
I’m sure Paul has done some good stuff, but he’s the closest Beatle to being lame. John, on the other hand, became even cooler after the Beatles. I think Yoko had a good influence on him.
I’m sure lots of people strongly disagree with what I just said.
Tina Turner, cool… Ike Turner… not so much
(Bolding mine).
I think you misspelled “heartless, abusive, inhuman bastard”.
Tina, OTOH, unreservedly cool.
Robbie Williams (cool) and the other members of Take That (lame-o).
Tommy Shaw and James Young of Styx versus Dennis DeYoung.
David Cassidy and Danny Bonaduce.
I have the answer the this question!
It’s the lead singer in The Monkees vs the guitarist
Look how cool the guitarist is with his composure, the riff, and even a hipster hat.
Eddie Van Halen (cool) vs David Lee Roth (lame)
Michael Jackson versus his 4 brothers of the Jackson 5.
I may be being whooshed here, but the OP stipulates former bandmates. I haven’t listened to Metallica in years, but is Ulrich or Hetfield no longer in the band, or has Metallica broken up? One would think that would be big news… >.>
To contribute, I’d say Justin Timberlake v. the rest of whatever boy band he was in. But the correct answer to the OP’s question is Van Halen v. Roth. 
Slash and Axel Rose.
I agree,Freddy was the ultimate in cool,but Roger aint exactly wearing a pocket protecter.(Or Brian for that matter)
Ok… Brian wears a pocket protecter,but when he does it,he does it cool.
Which of them is the cool one?