People apparently want it, so why not? Whatever helps them to make a more educated purchase. If they trust the reviewer it's fine. If they disagree with his opinion they won't follow his advice in the future. That's how recommendations work.
Music albums especially are a fickle thing. You will never know how it'll be until you bought it. A review can give you at least a general idea if it's the same as previous albums or something completely new and disgusting.
You know what's pointless? Complaining about music reviews on a gaming forum.
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