I find Amazon reviews helpful even though I know some of them are paid/compensated by Amazon (among other gaming of the system). The way to make the reviews useful towards finding what you want is to pay attention to the aggregate and ignore the outliers.

Fundamentally, reviews exist to help potential readers know if they should give an unfamiliar story a try. Once they start reading, it is entirely on their own perception of the story to keep them interested in reading. A high rating should not equate to readers becoming blind to the faults of a story they don't like.

I purposely avoid the "trending" or "popular" lists because I know that they don't tell me anything about whether I would like a story or not. I only pay attention to the rating after I've decided the synopsis and tags suit my taste (I'll admit to also paying attention to the cover, since I am an artist). Maybe I'm an outlier, but I like to think most people are savvy to the fact that ratings can be gamed (at any site) and reviews are not any type of absolute measure of quality. They are an indicator, perhaps a warning -- nothing more.

I mean .5 star reviews? Really? Pretty much nothing is bad enough to deserve that, but you still see it commonly. I've got some too. Yeah, I've seen some authors distraught over .5 star reviews, but I see it as just another part of the system you have to accept if you accept the existence of ratings at all. I try to participate in the system in good faith, giving what I think are reasonable reviews. I also want to respect the effort it takes to even create and release a story into the world (unpaid at that) in the first place. I know certain genres or tropes turn me off completely, so I just avoid reviewing stuff I know I am unlikely to appreciate. I think/hope most people are like that.

My personal scale
.5 star -  monkey with a typewriter
1 star - average middle school student
2 star - average high school student
3 star - competent amateur
4 star - promising talent
5 star - polished pro-level product