Thanks Angelus.
Reading your post, there's a couple of things I want to highlight.
One, I understand the argument you're making. I get it, in as much as I can as a white dude. Which is to say I can empathize, but probably not really understand. I am not reminded every damn day, as a POC might be.
Two, my view might be coloured somewhat by the fact that I am Canadian, and I live in Toronto, which is one of the most multicultural cities in North America (around 50% white). I do not see a lot of outright racism at all, although i do see a lot of 'soft' racism.
Reading your points, I am still of the opinion that the phrase "cultural appropriation" isn't particularly useful. I say this because I think (I mentioned this in the box braids thread) that this phase attempts to put a negative label on a phenomenon that is both a sympton of racism it's "better" when white people do it as well as something that I regard as a positive function of society, which is the intermingling of cultures from many parts of the world.
At the end, I arrive basically at the same place you do Angelus, albeit via a different route; you'd have to get rid of racism altogether for "cultural appropriation" to go away. Where I differ is in thinking that CA is something to get upset about. Now, I don't really get to make that call for other people, in a larger sense. I don't get to say whether or not someone ought to be upset. But I can question the validity of that outrage on simple terms. I think black people (to pick one example, a prominent example in N.A. but hardly exclusive-to) are justifiably upset for historical and modern reasons both. They are still treated as second class in many cases we have all seen the studies about resumes, names, all that. It sucks. Racism sucks. We agree.
But in terms of body image problems: these are not unique to black people. White teenagers test higher than anyone for bulemia and anorexia. Blonde, thin women are the standard for essentially everyone in western culture. Body dysmorphic disorder is not unique to black people. Mainstream beauty "standards" affect almost everyone.
In terms of other cultural artifacts: I remember this discussion when the Beastie Boys first appeared. I remember this discussion when The Police appeared, a bunch of white british guys playing reggae. I remember when Led Zeppelin was accused of ripping off blues music. And of course, the Beatles with their myriad (and loudly credited) influences, and then probably the original CA "example" which was Elvis dancing like a black guy. Elvis might be the only true example of CA. I see all of these as positive moves. No one accused Hootie and the Blowfish of cultural appropriation. The intermingling and mutual respect for a culture can only be positive, long-run, in my mind. I think it helps race relations tremendously in fact.
Another example I can think of is American sports. I think baseball, basketball and particularly American football have moved the needle significantly on race relations. To be crass for a sec, you just know there were and are a bunch of racist chuckleheads in middle America who have had their insular views of black people rearranged because we turned several black athletes into gigantic heroes and superstars.
Which brings me to this:
You are just talking about racism. Straight racism. There's nothing to do with the culture there. That is a misdirection, in my mind.
Your comic example, the geeks all bent out of shape because comics are 'mainstream' now? I think their anger is misplaced as well. They didn't lose anything. There are simply more forms available. And of course, of course, there are lots of black artists and musicians and fashion designers. Of course, there is money to be made there, of course everyone recognizes where it came from. But it shouldn't matter.
So you see, hopefully, how I arrive where you did we must get rid of racism via a different road. But this "cultural appropriation" phrase, which is typically used as a verbal bludgeon to say "you don't get it, you ignorant twit, check your privilege", is not particularly useful. You are yelling at an aspect, and it's all in the eye of the beholder.
Were I really into reggae/rasta culture say I loved the music and everything about that scene I would really have no idea how to "tastefully" engage in that culture, as a white person, without potentially pissing someone off. I would probably decide that as long as I wasn't hurting anyone directly, it doesn't matter.