This isn't a curve system. Gamers want to know from these scores if we are getting $50 or $60 worth of game if we buy it new, and for most games to be worth that, they should probably be scoring at least an 8, or if they made some forgivable blunders but are still fun, then a 7. One hopes all newly released games score in that range.
Scores of 1-6 can serve as a warning of just how poor value a game is. If, say, someone were a fan of a certain genre, but a newly release game is sub-standard, they might still get it if it is a 5 or a 6, but not if it scores a 2.
You may not like the current rating system, but it is functional.
Maybe the point of the OP is if there might be score inflation due to marketing pressures, but if so, that should be asked more directly.