You can change your review if you don't like what's happening with the game

It would take a significant number of people changing old reviews to make the overall rating drop even a few percentage points. Even if it did work out like the OP obviously would like it to, it wouldn't matter to most shoppers who would see a higher recent review rating score right next to it. It would just send the message that maybe things were bad earlier but have improved a lot. Its impossible to tell what message shoppers are going to see in the review ratings.