We can actually prove it but problem is proving something in "west" equals to "documents", unless review companies and "influencers" willing to share those, which are i am sure protected by non-disclosure agreement.
I didnt say i dont believe 81 rating is impossible. Look at indie games with no budget in marketing. Company i worked in Kiev, always provided accounts to us for example, we just had to create an organic text, since market during that time was flooding with machine text.
Not sure how steam review works, i can still see Product refunded reviews, you mean their rating is not added to percentage?