I think all you said must be true. I just wonder what they could do about it? Better ML models to identify ad click fraud? Get rid of reviews altogether?
Yes, it's expensive and carries its own risk of corruption and insider fraud, but either Amazon polices itself or others will police it, and they will be less kind on the organisation as a whole.
If Amazon manages to get a reputation among the public for fakes (rather than just us, a specialised audience), it will be extremely expensive and hard to shift.
Not allowing reviews from people who never purchased the product would be a start.
The next level would be no reviews until the product is actually delivered.
One more level up, no reviews until a reasonable amount of time post-delivery.
Yet one more level: Require contacting the seller with grievances before posting a review.
I would also add a finite impulse response filter to reviews in order to control rate of change.
Rapid negative review posting rates should red flag and rate-limit these review.
Also, the star rating math has to change. If you get just a few negative star ratings it can absolutely sink your listing. Unless you have thousands of positive ratings the math is such that a handful of one star reviews will destroy you; requiring hundreds of 5-star reviews to counteract.
The battles being fought behind the scenes on Amazon are beyond what anyone would believe.
Someone can take out any competitor instantly by making a few fake quality reports to Amazon. It’s insane, really.
What do you think would have helped?