So the way it works is that some company makes a page for a stuffed animal for example. They name the product page appropriately and start selling their toys. They push hard and gets lots of reviews and build up the aSEO (amazon search Optimization) for that page. They build up 1,000 positive reviews for their stuffed animal averaging 4.8 stars. Cool.
Now they decide to stop selling that toy and instead start selling fidget spinners. Why start from scratch and go through the work of building up all those reviews again and the aSEO that took years on the stuffed animal product. Instead they just go in and change the title, the URL slug and the images to represent the new Fidget Spinner. They publish the changes and now, within seconds of posting their new Fidget Spinner is one of the best reviewed fidget spinners on Amazon and starts immediately getting sales because the page has strong aSEO and high reviews which makes it present well in search results. Visitors of the page see the high reviews and buy the product. They start selling thousands of Fidget Spinners overnight and build up to 2,000 positive reviews.
Now that company sells fidget spinners and then gets sued for using toxic glue in the building of their fidget spinners. No problem. THey change their name from SpinnyAltodaWidgetCorpIncUnlimitedPlus to ShenzenSpinnyWidgetToyPlusUnlimitedCorp. New company, now you can't sue them. Then they change the name on the product page and keep selling the same product with a different name and same reviews, building it up to 3,000.
Now the company goes under. But they have all these high performing amazon pages. Here is where the fun begins, they literally go up for auction. Companies will page hundreds of thousands for a top performing amazon page. They sell the page to the highest bidder. Now a new company ShenzenShitzuSuperCorpPlusMegaChargerMorePlusPlus buys the page and starts selling Fish Oil supplements. They just change the name, images, URL, and company information, but it is technically the same amazon page. Then they start selling Fish Oil supplements with 5,000 reviews averaging 4.8 stars. They immediately shoot to the top of the search results and start selling thousands of bottles overnight because people are overwhelmed by the positive reviews of this product and its age and legacy on Amazon tells Amazon to push it to the top of search results.
This is the black market of Amazon pages. These pages change hands often many times a year. Amazon could easily prevent product changes above a certain threshold or even across categories to prevent or eliminate this, but they don't want to. They are complicit in these behaviors by turning a blind eye to what they know is happening.
Here is a detailed article about Hijacked Reviews from Consumer Reports: https://www.consumerreports.org/customer-reviews-ratings/hij...
For example, in one review they find a phone charging cable that has reviews for zip ties, hand soap, shaving cream, and gaming headsets all in the reviews for a phone charging cable. This page has been hijacked several times by entirely different product types.