Those are valid arguments ... coming from the privileged "hindsight" position ... from whence we are able to observe things that have happened in history with a kind of distant clarity that's never really experienced as such by those who are present when the actual shit goes down. For instance, what does "plagiarism" mean? Case in point, the first (self-titled) album by Rush ... which upon its release was considered a "Led Zeppelin rip-off product" by a number of critics ... and that seems both harsh and unreasonable in hindsight, but you can sort of understand what point they were trying to make, at the time, in that "the sound" is somewhat similar, or at least so much so that it's fairly likely that people who like Led Zep will also like said Rush album (and of course also all the others that were accused of riding on the coattails of Zep's commercial and artistic success, at the time).
It seems rather obvious that development in music is a lot about "cross-pollination" ... that is to say, musicians picking up ideas from other musicians, by way of listening to their music and finding inspiration in that ... and when a bunch of people seem to be aiming towards the same relatively narrow interpretation of some aspect of "the sound" that were originally created by some artist, that which we call a "genre" crystallizes into manifest form (particularly if and when this includes a lot of enthusiastic fans). When you get old, like me, you will see things differently. Instead of seeing for instance "power metal" and "grindcore" as two distinct genres, you might rather think of them as same-same, but different expressions of the same basic business idea, which is "rock'n'roll". Then you might move on to think of the entire "hard rock" genre as a species of its own ... with its own distinct history ... which brings me back to the admittedly somewhat tongue in cheek "footnotes" argument: Nobody will seriously bother to argue against the common idea that "metal" was invented by Black Sabbath ... but even they existed within a continuum of ideas. (Let's not forget that Robert Plant and John Bonham were both Brummies, meaning that all of Sabbath and all of Judas Priest, but also half of Led Zeppelin, were of the relatively same age and background, from Birmingham, UK ... meaning that it's hard to argue against the importance of that specific city in our line of business.)
With regards to Whitehead, as mentioned in the OP, he was of course no fool. He never meant to say that Nietzsche and Bergson, Dilthey and Gadamer, were all the same ... three blind mice stumbling along the footpath laid down by Plato ... yet that was exactly what he kind of did, which, in an imaginary stand up comedian club for philosophers, would have everybody thrown into a fit of giggles. In my opinion, the "rock star" aspect of metal is at the very least a template that were created by the Zep. They had an attitude which were ever so slightly slightly larger than life ... and the audiences ate it all and asked for seconds. Nobody who are of an age and disposition to go and experience the Zep live on stage in their prime, have been unaffected (give or take the occasional blowhard, because there's always somebody) by the magic. You need to count among them a lot of people who would later go on to become major influences themselves. Such as Paul Stanley from Kiss ... and let's just have it out and on the fucking table: No matter what people may think of Kiss, it stands as undeniable that they were a heavy influence on MY generation, including (but not limted to) people who went on to become musicians themselves (and are today between 50-60 years old) ... who later said, in an interview, that he saw the light. He understood what he had to do. When Paul Stanley saw Led Zeppelin live on stage, the seed that was later to become Kiss got planted. Perhaps it would have happened either way, this or that, but it's a fact that this is the story told by Paul Stanley. He credits the Zep for making him want to become a rock star.
Anyway, I'm babbling ... but this is the "deep" department, so you get what you came here for. Tony Iommi also have a story to tell, which is -- importantly -- that his major source of inspiration for his guitar playing was Hank Marvin. That had me go "but of course" when I first heard it. Tony uses lots of fuzz and drop tuning and whatnot ... but his overall "picking" is not at all unlike that of Hank Marvin. It's funny, really, who influenced whom, to do what, when and where. Take for instance Lemmy. A hard core rocker if there ever was one. He said time and time again that his personal influences were the old guard. People like Elvis, Little Richard and Eddie Cochran. He wasn't necessarily that much "into" any of his contemporaries, although he said of course ideas are floating hither and thither. C'est la vie. It stands to reason, such as I see these matters, that the "rock star" template was laid down by the Zep ... and enthusiastically replicated by those who would later follow ... but saying this isn't the same as saying that Led Zeppelin was a total product (although many say so) ... because there's no denying their talent.
However that may be, I'm not really concerned with "being right" (I hardly ever am) but I like to discuss ideas. Me liking metal (and/or the greater genre of "rock'n'roll") is a matter of the heart, of taste and preference which originates in parts of me that I neither can nor will even try to explain. It is what it is. And that's all it is. Just some quirk, some funny bone that gets tickled just right by the fuzz ... which has me going "oh hell yeah" where others will go "OMG that's awful!" even though we are observing the exact same thing. De Gustibus Non Dispotandum, said the Romans. There's no accounting for taste. Many years ago. I was in a band called MDK. ("Mother Daughter Killfuck") I'm fairly certain that none of us would have thought any of what we were doing were even remotely related to Led Zeppelin. Our principal idea was to be harder and heavier than everybody else ... which is about as uncommon as trying to stack and groove the E-A-B chords during a blues jam (just listen to any Allmann Brothers live recording). However, I'm not even sure I'd be as much into "music" as I am if it weren't for heavy rock and metal. Seriously. I do of course like the 1812 overture and whatnot ... Wagner and Shostakovitch ... but that doesn't explain my taste for rock. There's something else, something more. Like a spiritual thing. Like connecting, with something, somehow. The famous click. Am I making any sense now? I'm trying to fish for that "click" moment. Like when you just know. Like when it's def: "This is some sick shit man! This stuff kills!" You can feel it in your bones. It just hits that spot. It all falls nicely into that groove ... which some say were created by Led Zeppelin, for nefarious purposes of varying orders, such as polluting the youth of America or bringing about the fall of the British Empire ... but those people were never good thinkers to begin with.
I should end now. Literally, this is written during a break from writing something else, which is more in the region of 1000 pages, so I'm already in the mindframe of "writing a lot". However, I hardly ever think I'm "right" ... it's rather a question of being a little less wrong every time. Or circling the target like a drunk person trying to perform at a bow and arrow game. Your one and only possible advantage would be awareness. You know where you are and what you're doing ... so carry on. You may not be helped. It's swim or drown now, dear. Sorry about the inconvenience but enquiring minds want to know.