Amazon reviews are about as useful as Youtube comments. You can read them for entertainment but don't expect anything useful about the product, and don't base a purchase decision on them.
I always look at negative reviews. From those you can tell if there's a consistent concern, if someone got a fake, or if there was just a preference mismatch for someone.
I still trust 1-star reviews more than 5-star, but I don't take them as gospel. As you said, if there is a consistent message across all the negative reviews from a mix of reviewer types, then it strengthens the signal quality.
Buying online sucks :(