Your observation of the preponderance of unreliable reviews on Amazon matches what we see across the board. Unfortunately, ever since Amazon opened up to 3rd party sellers, the reviews have become a marketing tool by a lot of these sellers to move ahead of other products. These sellers use everything from pure fake reviews to gamed verified purchase reviews. This is major reason why so many reviews nowadays are unreliable, it is truly a wild west out there in the eCommerce world and fake reviews can mean $$$.
With that said, we just launched Fakespot Guardian as part of our new Chrome extension which solves the 3rd party seller problem by telling you if a seller is reliable or not. By knowing if seller and reviews are reliable, you will be able to purchase anything with confidence.