I have been both sides of this debate - I have written reviews and I have of course bought stuff based (partially - I ain't that stupid!) on reviews.
On the writing side - star or points ratings are impossible. You soon run out of numbers or points. I wrote plenty for audio and video mags and our agency wrote many more for other fields.
Camcorder Magazine started having ratings and as soon as digital camcorders came out, they all had to have five stars as they all out-performed the old analogue boxes. So the Canon XL1 gets 5 stars - and then the Panasonic EZ1 is even better - so what then? Six out of five?
Then HD, followed by 4K and now 6K and 8K and large-format sensors? If the shitey little EZ1 in SD gets six out of five, how many does the 6K Eva-1 get? 20? 30? Do you then have to give the Arri Alexa-LF 50 points?
Reading reviews - Hugh Ford wrote credible reviews in Studio Sound and Hugh Robjohns writes the only reviews I actually believe today. The rest from cars to cameras and from lenses to lights are probably mostly pretty worthless. There may be some I don't know about but I ain't found them yet. It may have something to do with the name Hugh - just a theory!
I recently had to buy a set of cinema prime lenses. Prices range from £1.500 to £30,000 per lens and one needs about five. If you read the reviews, you would think that the £30,000 lenses are so wonderful that only a fool would try to shoot a movie with anything less.
Results of schlepping around showrooms and using the studio of a cameraman friend and neighbour - I tested Arris, Cookes, Zeiss, Canons and Xeens for smooth bokeh, detail, distortion and skin colour. The best were Arri Signature Primes (2nd most expensive) and the 2nd best were Xeens (the cheapest!) The worst by a considerable margin were Cookes and they most expensive and always got the usual rave reviews.
As five Arris would have cost the best part of £100,000, I got five Xeens instead! Obviously! With the notable exception of the Arris, the order of merit was in reverse order of sticker-price! (That was especially true for skin colours.)
In audio - where do I start? Cameras and lenses are easy - all you need is a set of eyeballs, some test cards and some common sense, but how many punters have distortion meters, sig-gens and oscilloscopes? Just how many can trace the impulse response of a mic-pre or a speaker?
And then we have all the 'snob-value' name-brand products that seem to be carrying price-tags that have little to do with quality or a rugged build.