Reading reviews without being steered
Fake reviews are banned and paid ones must be disclosed. That settles less than it sounds - most of the steering is done with genuine reviews.
More is regulated about reviews than most people realise. Posting fake reviews, or commissioning them, is prohibited. So is an undisclosed paid endorsement. And a shop that displays reviews must state whether and how it checks that they come from real buyers. That disclosure is rarely prominent, but it is there, and it is the first thing worth looking up.
That sharpens the question beyond "are these reviews real". Because most of the steering is done not with invented reviews but with genuine ones that do not say what you think they say.
Received free is not fake. Programmes where a reviewer gets the product free in exchange for an honest opinion - Amazon's Vine is the best known - must be labelled as such, and they are. Those reviews are not bought and are often more thorough than average. But someone who paid nothing is not weighing the price, and price is half of any verdict. Read them for the description of the product, not for the conclusion about whether it is worth having.
Watch the dates and the volume. A hundred reviews in one week on a year-old product is a campaign. Five years of reviews arriving steadily is a history. Sort by recent: for electronics and appliances, what people thought last year is worth more than what was written at launch.
Check that they are about this product. On marketplaces, reviews are sometimes carried over from another item that shared the listing - a different colour, a different model, occasionally something else entirely. Four stars from two thousand reviews, half of them about a phone case while you are looking at a charger, is not a review of that charger.
Read the three-star ones. Five stars says "pleased" and one star is usually about the delivery. The useful material is in the middle: people who are keeping the product and still have something to say about it. That is where the things you only notice after a month get written down.
One last practical test. If the complaints you find are all about the same part - the hinge, the battery, the app - you have a pattern rather than an unlucky buyer. One angry review is an anecdote; twenty naming the same weak point is a product description the manufacturer did not write.