Well, regarding the Reznor-Cobain discussion, I can only tell you that in one of my first discussions on Debaser, a couple of years ago, I found myself defending Trent against the classic alternative-carbonari and those who "listened to him before he became famous," accusing him of having massified and trivialized the true industrial culture of Foetus and Ministry at the altar of the dollar god. Reaching a wide audience intelligently and without compromising one's art remains a great achievement for me; I’m not a fan of the sectarianism of alternative-Hindus, even though among my idols, I have many brilliant outcasts and losers, from Bruce Palmer to Greg Sage himself. I prefer Jay Mascis to Cobain: should I be snobbish just because Kurt sold three times the records Jay did? The wave brought by Nevermind was certainly a short-lived revolution (Restoration wasn’t far behind; the industry takes over everything: the hope of building an alternative society to capitalism based on music has faded since 1969; there's not much to do), but for me, it indelibly marked the spirit of those years, representing the USA and Western society from the perspective of a "Teenage Wasteland." After all, rock is a flame that has always burned quickly. How long did punk really last? The 40 minutes of the first Sex Pistols album. The wheel turns, and as someone said, those who stop actually fall behind.
It’s quite clear that if you define "implosive" Alice in Chains (some implosions are welcome, especially after creating albums like "Dirt" or "Above" by Mad Season!) and "never born" Mudhoney (true pioneers of the scene), you have a marked idiosyncrasy towards the term "grunge."
<< putting Soundgarden in the grunge category was even comical since it’s clear they resembled groups like Black Sabbath far more than the American indie bands from the late '80s that were supposed to be the genre’s inspirations. >> But have you ever heard "Bleach"? If that album isn't indebted to Black Sabbath, with its dark thicket of heavy riffs, albeit reinterpreted through the prism of Black Flag... grunge isn’t a precise style (just like the post-rock or trip-hop you mentioned), it’s a powerful term born to best define the pastiche of metal, punk, and psychedelia that many practiced in Seattle, within various peculiarities. In this "style," Soundgarden were the undisputed masters; we could use our friend Black Dog for an erudite exegesis. Musically, I believe the Seattle bands are still a source of inspiration for many today; just ask AlessioIride and his band. Certainly not the only one, because at that time there were also many other excellent scenes (post-rock and stoner, to name the most obvious ones), but the "Seattle Sound" is far from having been homogenized and digested: just think of how many reviews are on this site. In short, grunge was certainly a social phenomenon, but it was also a musical story of great success.
Regarding the attitude of the artists, I prefer artists who question the contrast between art and business, perhaps amid thousands of contradictions, but at least sending a message of ethical integrity. It's too easy to say, "we're in the game now, so let's dance" and accept any nonsense from the industry, like sponsorships for clothing, exclusive distribution contracts with Auchan, or selling one's art for a TV commercial, as even Dylan did. Then you believe that commodification and grunge travelled on parallel tracks, due to "compromising media contaminations": good for you. Tori Amos, however, doesn’t seem to have batted an eyelid when one of her songs remixed by Van Helden became a club hit; the royalties must have settled any ethical doubts. The same happened to Nirvana, but posthumously to Cobain, who would certainly never have authorized such a travesty. Then you talk to me about trip-hop: but if at a certain point in the '90s you saw the Veline of Striscia la Notizia doing their semi-nude dances with that music in the background!!!!