Judas Priest are certainly Metal. Some people, like Mick Wall, considers them the first 100% Metalband (with the release of British Steel). What I'm saying is, whatever classical influence, came after Heavy Metal had cemented itself. And minf you, that Heavy Metal stemmed from the Hard Rock like Zeppelin, The Who and AC/DC etc.
Yes, I totally agree that Metal wouldn't have sounded exactly the same, but we would still HAVE Metal - That's what this debate was originally about! The Flash claimed Metal wouldn't exist without classical!
Also, about Jazz being influenced by classical? Sure, I guess in the form of instrumentation, but the reason they used standing basses and cellos is because that was what was around in the early days. It wasn't because they listened to a Classical concerto and thought, "Wow, I want to play these instruments too, but as a jam!". It's because they were the instruments that were around. So in terms of instrumentation, yes.
However. Jazz and Blues came from African Americans. The early Jazz and Blues (their origins are the same. I like to view early Jazz as Blues improvisation: The basics of Jazz is to solo over a given chord sequence. It also contains a lot of Blue notes, as in, the Blues scale), as in the original Jazz and Blues sound, had virtually nothing to do with classical either. It was the poor man's music (and was despised by the people of higher social stature).
Edit: Hold it while I read through your edited post!
Okay. Yeah, he's basically talking about Ritchie Blackmore as Yngwie Malmsteen. As I already stated, Ritchie incorporated minor classical influences. But was in essence a blues rock player. He mostly played pentatonics. Now, about Smoke On The Water: Until the 20th century, the 4th interval was perceived as dissonant. Classical music used it, but to create tension (not sure about renaissance though!) Over time, that changed and it's not viewed as consonant. Anyways, back to Richie. Smoke on the Water is built upon intervals of 4ths - That's something he got from renaissance music. But as I said, he was still in essence a Blues player.
I can't speak for Van Halen, but I said I excluded Neo Classical, for obvious reasons - Which is the sub genre Malmsteen created (and Rhoads was, after the creation of the genre, viewed as a Neo Classical guitarist too).
Also: Feel, texture and creativity. That's not really saying that much about the music, does it really? Texture, I guess that can translate into song structure (that's generally applicable to Progressive Metal Bands (and some, like, a bit, Iron Maiden), and Death Metal, which is much more freeform when it comes to structuring - Death Metal doesn't follow the ABAB form like most pop and a lot of Metal does). But creativity and feel doesn't really say much about how the music sounds - It just says that it can be very creative (which Metal is! It has a shitload of sub genres almost unlike anything else). It doesn't really say that they are similar. At all.
). 
I have repeatedly said that he incorporated elements of renaissance, but he was in essence a blues player (which is something I recall Yngwie has said too - That's what got him bored of Purple! Too much blues). And I also said I excluded Neo Classical, which is a sub genre and has inspired most of MODERN lead guitarists (however - What made people attracted to Malmsteen is really the blazing skills and speed! Not the use of Bach chord progressions, Phrygian mode and Harmonic Minor and diminished chords - Although they are part of his sound, it was the skills that made people go "wtf?"). 
