How Amazon brazenly rig their ratings to promote books pushing fake black history

Amazon delete unfavourable reviews on their site of books by black authors; especially ones which set out an alternative history of Britain in which black people played a key role.
https://www.amazon.co.uk/Black-Time-Awesome-Britons-Yesterday/product-reviews/0241532310/ref=cm_cr_dp_d_show_all_btm?ie=UTF8&reviewerType=all_reviews

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