Every generation or form of game journalism is biased and favoring to certain things each generation. Game journalism tends to go far more to what the consumer wants then actually giving good unbiased feedback on the products.
Take for instance the defunk magazine EGM, when the PSX/N64 era was out they were all for RPG's and gave most of them good reviews, while when the PS2/Xbox/GC era, most RPG's were reviewed poorly and even games such as True crimes were given good reviews and now anything which doesn't have a gun in it has to be viewed with a different approuch.
Also, we're now thinking about playing for the home team more then before, since Video Games were predominately focused with Japan. if you give good reviews to American products or American Games, more Americans will buy those American products over the Japanese ones. That's why you see far far FAR more publishing companies citing the death of the JRPG genre, even if most people wouldn't have bought those games in the first place and the genre have mostly been niche since it's beginnings in the state.
it's all roughly subjective but the flavor of the month really influences what the hell they are going to say is good and what isn't. Remember when Halo 2 came out and NO ONE said the single player was shit? it got glowing reviews from everyone and they all gave it perfect scores even though the single player mode was a piece of shit.