This is one of my pet hates, why have a 0-10 scoring system and only use 8, 9 and 10.
The usual excuse is that they only report on stuff they they think sounds good, other stuff gets left on the cutting room floor. Cynically, the magazines and websites have to make money and they do this through selling advertising, often by companies that they are reviewing and so there may some pressure (real or subconscious) to not alienate potential sources of income.
Finally, it could be that everything produced these days is very good and there are no turkeys out there so whatever you buy will sound at least good if not excellent.
There ar some sites out there that are not afraid use the full range of scores - Angrymetalguy is one such site, he/they occasionally give out 1.0/1.5 (including one this week), most often 2.0 to 4.0, occasionally 4.5 and only awards a 5.0 one every year or so.