Human intelligence still has some value
It's really hard to take seriously anyone who defends the spammers. The best possible interpretation is that you're some kind of religious fanatic with "Live and let spam" as one of your commandments. I could answer each of your objections in some detail, except that it's obvious that if you actually read what I wrote (and I have to doubt that), then you certainly didn't think about it.
Just for the sake of illustrating why it is better to say nothing when you have nothing to say, let me spend a few seconds to consider your first "thoughtful" objection (all sarcasm intended). Do you understand the word "integrated"? Evidently not, so let me explain that word in the original suggestion. Because the system I proposed would be integrated into the email system, the authentication is exactly the same as that which applies to each user of the email system. I will go even farther and say that a good (as distinct from a minimally competent) implementation would consider the history of the reporter. An additional hedge in the particular paragraph you mentioned was "few", but I've already wasted far more keystrokes than your minimalist comment deserved.
Instead, I'll throw out another example for consideration. This one is slightly more complicated, so please don't strain yourself. Just a caution judging by your previous reply...
Recently I received a notification from American Express warning me about a new security problem. There was only one minor problem there. I am not now and have never been a customer of American Express.
This was a quite beautifully done phishing scam. I spent several minutes studying the masking, but I acknowledge that it was done at a level I could not unravel. The cover letter was doing some highly clever JavaScript manipulation, probably playing with the DOM tree, and the main body was actually an embedded and encoded HTML webpage that was intended to run locally. As paranoid as I am, there is some chance I could have clicked on the trigger, especially if it turned out that I was an actual customer of American Express.
With the anti-spammer mechanism that I am suggesting, the first round of analysis would flag it as a phishing scam, but a later round of analysis should escalate that report to a fairly high level of seriousness. I'd even want to believe that American Express might want to initiate countermeasures to protect their actual customers.
However, it could go even farther than that. What if the spam included valid personal information? In that case, there might be an actual breech of the company's servers and the actual customers may be part of the mechanism to alert the authorities.
I'm not saying we can create a perfect world free of spam. I'm saying that spammers (and to a lesser degree, the spam-loving defeatists) deserve a full load of trouble, and I'm eager to help pile it on top of them.