I would use them as a general guide rather than a rigid one.
The weight rating is for the absolute maximum loading per tyre, which you'd likely never get near, but you HAVE to follow as per your car's handbook / inside door plate. A tyre can be fitted that has a higher load index rating than the minimum stated there; similarly with the speed rating.
The noise rating is externally measured noise, not in the cabin, and thus what you hear is more dependent upon your own car's soundproofing, or your driving style and what roads you drive on, plus the weather conditions.
I do recall someone here previously noting that the mpg one essentially saying the difference between each band (at the mid point) is a small percentage, so realistically you might only notice a difference between tyres 2 or more bands apart. Don't quote me here, but I think the difference between an A and an E or F rated tyre for mpg was about 20-25% - for the same test vehicle.
I suspect the same would apply with wet weather performance, noting that the actual mpg and wet (and dry) performance of you car is as much dependent on the car itself and your driving style as it is the tyres.
Some tyres, despite them being A/A or A/B rated, often work poorly on certain cars, but very well on others, hence why they are subjective ratings in my view.
The wear or traction rating (on the sidewall only these days) is more of an American thing, and again is a general guide like the others - a large difference in rating between tyres would likely be noticeable; a small one would likely not be.
For that reason, it's why I always take note of as many user (us) reviews of tyres*, particularly matching my own car (or failing that similar ones) and a tyre I would look to buy as much as just a car magazine tyre test. Luckily for me, most of the latter use a VW Golf, Audi A3 or Ford Focus car, which reasonably matches my Mazda3 in most respects.
* See the Tyre Reviews website - Jon there is very knowledgeable and often carries out his own group tests as well as republish car magazines' ones, plus he will always respond to queries via his YT channel or the TR comments area below each article (the site uses Disqus for a comments platform)
[update] If the OP is possibly referring to tyre group test 'ratings' by car mags and others (like Tyre Reviews), again, they are subjective because they are almost always carried out on (nice smooth) test tracks and using new(ish) cars, mostly VW Golfs or similar. What works well for them may not for the OP's car, or vice versa.
Hence why the user review on Tyre Reviews can be just as useful. Just take note of the variable each person states when uploading their review scores, because many upload them with only a few hundred miles/km on the clock after the tyre change, or their driving styled (which should be listed) may not match ours; similar the car they drive can make a big difference, or the region / country (weather, road quality).
Edited by Engineer Andy on 13/02/2022 at 18:54
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