Actually the HN community is politically deeply divided. Complaints about its bias thus tend to contradict one another. For example, https://news.ycombinator.com/item?id=7630388 says much the opposite.

Many flags on political stories and flamewars come not from users with opposing politics but from users who, regardless of their politics, don't think HN is the place for them. It's a "pox on both their houses" thing.