Not necessarily wrong. If a story has all 4s and 5s, then a bunch of 1s come in, they are likely either tactical or spiteful, sending a message rather than being an honest evaluation.we can't understand why someone would hate them enough to drop the dreaded 1. So any score of 1 or 2 stars *has* to be trolling, surely?
And rationally we understand that this is wrong,
In a lot of sports where the performance is graded by a panel of judges, it is common practice to throw out the highest and the lowest and average the rest. It's often used in stats generally to normalize out the outliers that could be due to any number of factors outside a true measurement.