The rating curve in gaming is steep and getting steeper. For me, a 7.5 is the equivalent to the original Assassin's Creed game--colorless, monotonous, repetitive--I didn't finish the game.
The things is, people want instant gratification and I think review scores fall into that category. It is much easier to see an 8/10 than read a 1000-word article on why it gets an 8/10. Having said that, I appreciate that some sites now have video reviews. I myself prefer to watch a video that justifies a score than read, however, I still occasionally choose three or four articles from reviewers that I trust for games that I'm excited about.