This is precious: a Who fan registering to the Led Zeppelin site in order to troll complaine about the behaviour of the pesky Zep heads ?
Seriously? Because my perception is different: on every music forum I visit, there is not one "Vs" thread involving Beatles, Stones, Zepppelin, Floyd, Purple that is not having the mandatory Who fan shouting "The Who is better than both" (if you don't believe me, show me some examples of Zep fans infesting debates about Who Vs .., and I will show you the same amount+1, the other way around).
I know, the inferiority complex might be immense for a band that in the 60's was put by someone (the Rolling Stone Magazine? I can't quite remember) alongside Beatles and Stones as the great triumvirate of rock, but got left behind in the stardom by the two .
Even a bitter Townshend said once that they (Zep) "became so much bigger than The Who in so many ways".
If you look in the review mirror, the Who have some golden past (in the 70's the music magazines loved them, they were revered by the media as innovators; they were loved by the punks while the other rock acts of the time were despised) but they kind of lost the momentum, while Zep just got bigger and greater, seizing more and more awards and accolades and being recognized by more and more music artists and journalists as one of the most influential band of the century.
Actually, now Zep are ahead in the awards departament, having The Polar Prize (called also the "Nobel Prize for music")
Zep didn't have to play the Super Bowl or lease songs for TV shows and computer games in order to avoid sinking into oblivion: every movement they do generate enough buzz and cashflow to keep them visible.
Cultural impact is not just having your song played on CSI: is having your name in the public conscience. IMO there is more cultural impact in being mentioned by Al Jazeera, or by the president of Russia in an informal meeting, or by the president of Venezuela, than in having your song heard by millions that not necessarily know your name.
I'd say that the "No Stairway" sign in a popular movie proves a huge cultural impact - Zep is generating memes!
Comparing individual musician's skills can go either way (but as greatness go IMO Page>>>Pete, Entwhistle >JPJ, Plant >> Daltrey and Bonham<>Moon)
(and I'm not counting my dislike for Daltry's voice -that nasal tone, like he have polyps, annoys me at maximum level- cause many people seems to enjoy it)
But what sells the deal for me is the music:
In Zep's music I like the sound: complex, layered but with a firm structure at the same time. And that's normal for a band with such a tight rhythmic section.
With Who's music I have the impression of chaos: a simple melodic line ("most songs are singable", as a poster noticed above) on top of which Moon and Entwhistle are showing off their skills. And that's only normal for a band with such a flamboyant drummer and bass player.
And it's a matter of personal taste which kind of music you like better. I can't go past the "manufactured" vibe emited by Who's music (like, after they (Pete) come out with the basic song, they start to ornate it with musical flourishes); Zep's music seem to be born synergic.
But to say that "this" ot "that" Who song is "more complex than anything Led Zeppelin did" (and I saw this written many times) is outrageous: how can anyone say that, when they uses different time signatures, microtones, polyrhythms, polymeters (and I'm sure our musician fans could add more)
And don't start with the "original songwriting": I see more resemblance between Louie Louie and I Can'e Explain than between Stairway and Taurus
In the end, Zep remains the most proeminent rock figure of the 70's, driving the Who fans crazy because they think their band is better.
Simply as that.