This just isn't reliable. I tested in on the Amazon Echo 2nd Gen, it gave it a D grade, 45.8% low quality reviews, half a star.

The two unreliable reviews I checked were two-star reviews, they were not high quality reviews, but they weren't "fake". For example one complained that they thought it was wireless, but it requires a power cord.

I checked the product's two star reviews (6% of reviews), the reviews I saw were all legit. The were long reviews, mostly complaining about the sound quality compared to the 1st gen. For reference, the top 5-star review also says sound quality was poor, until after the third firmware update.

Amazon isn't paying for fake reviews of the Echo, and no one would pay someone to purchase a $79 product (verified purchase) and give it a two-star review.