I only start paying attention to ratings when at least 5 or more people have rated, before that I'll play the game if it is to my liking.
After a game has 5 or more ratings, I'd say my general cutoff is around 2.5 stars. For me to play a game at or under this, the game either has to have some of my niche tags or cater to my tastes in one way or another. Around 3 to 3.5 stars I'll still investigate a lot of info about the game (tags, length, screenshots, grind, bugs etc) before I take the plunge. And then 4 stars and up I'll basically try anything, as long as it doesn't have any bullshit mechanic or too much grind, and doesn't have any cursed tags.