I’ve seen 3 ratings for you in the last month timeframe. That’s definitely enough to move it. I suspect a few others fell down from lower ratings due to increased scrutiny from uninterested audience members though (although I have nothing to back that up with.)
Just one rating can tank a game. I can think of many people who had highly rated games until it was ranked by a one star or two star vote.
We do keep an eye out for malicious voters and remove their votes, but sometimes it’s just the way it is. One person gave my game absence of law a three but gave counterfeit monkey a four, so that seems reasonable (I do feel like being one star less than counterfeit monkey is reasonable). I had a friend give one of my games two stars and it went from third place on my personal page to sixth, but they had valid reasons.
If we had more voters this wouldn’t happen but then we might encounter review bombing like happens on steam or IMDb.