This seems... like a bad idea. I don't really know how else to put it. Ratings are already such a subjective and sometimes reductive practice. I'm not sure what good would come of this? Apparently if you're given a bad review, it gets sent to you first and then you can contest it privately with the reviewer, but I don't see that as going well either.
@veronica this idea has been tried many times, and typically fails — for the reasons you've mentioned. There's just not enough incentives in the world to keep people on their best behavior, and when given the chance, without shared context, people will tear each other down. This is why reputation.com and more exists (I don't like reputation.com; only mentioning them because they illustrate my point about the secondary market that exists to "hide" negative information from Google and elsewhere).
I'd love to have @Kazanjy come and talk about his previous efforts to build Unvarnished and then Honestly.com.
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