I’ve only ever heard of it happening once and I honestly don’t know why they did that. It certainly didn’t change anyone’s mind. I would normally say that doing something like this without disclosure is unethical, except individual user reviews typically get so little attention in general that it’s highly unlikely that posting a single user review would make a difference. It’s super rare for people to actually read user reviews for AAA games - most of the time, people arguing about whether a game is good or not use the aggregate user score. It is fairly rare that user reviewers actually develop some kind of real following of people who care about their opinions on things. Any dev who did so anonymously would likely not have any kind of such following.
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