The key point is that punk had thrashy solos before thrash even existed. You go on about the subtle influence of jazz, classical and blues, but you miss the punk influence that is staring you in the face. There are virtually no blatant and overwhelming classical or jazz influence visible in metal, and by the time the 1980s rolled around most metal bands weren't listening to much blues either. The punk influence is staring you right in the face, but you focus on lesser element like the scales used in the solos. Take a step back and look at the overall picture of thrash metal; the speed, the aggression, the blatant political themes, even where the word "thrash" comes from. All things that were done by punk before metal.
Metal changed in the early 1980s, and punk was the catalyst. Unless you have proof that it was something else, and not just a bunch of wild theories based on your own obvious ignorance of the subject...
Also, I would be interested in hearing your response to my other points that you have appeared to ignore. Particularily the cover song issue. Quite a coincidence that a bunch of bands start a genre (thrash) that sounds awfully similar to the punk music directly preceding it, and then covered a bunch of punk bands, isn't it?
I'm not sure how this is being construed as a zero sum game where bands can
either be influenced by 'punk'
or they can be influenced by classical/jazz/folk/whatever, but they can't possibly be influenced by both. It should be obvious that jazz, classical and folk were all significant influences on metal from the get go, given the frequent allusions to all three in the Ur-metal band, Black Sabbath. It should be equally obvious that later metal owes a good deal of its riff lexicon and most of its rhythmic punch to punk, crust and hardcore.
This too, was true almost from
punk's inception: can anyone honestly say that "Exciter" would have sounded anything like the song we know and love if punk hadn't burst into the popular consciousness just a few months before? And we're talking JUDAS PRIEST here, not some crusty underdog from the lower tier of speed metal.
On the flipside, the very same album includes "Beyond the Realms of Death," a song that not only includes severally overtly neoclassical gestures, but is very much an electrified version of a sort of British folk music that ultimately derives from the tradition of formal court ballads (usually tragic) of Tudor and Stuart England.
And really, what
was (and is) pretty much all extreme metal from Slayer on if not the melding of the rhythmic intensity of "Exciter" with the epic sensibility of "Beyond the Realms of Death" - that is, the melding of the 'punk' influence and the classical and folk influences? Hell, go check out some of the classic Slayer interviews of the early and mid 1980s, When asked about their biggest influences, they rattle off the usual metal suspects - Iron Maiden, Judas Priest and Venom -
and D.R.I., Dicharge and The Exploited,
and Bach and Beethoven. I don't know if it gets much clearer than that.