Because Wikipedia vandals use those opinion pieces as citation.
Read the article I linked above when you have time. It’s about how radical feminists vandalized the Wikipedia page covering the Gamergate controversy into a one-sided narrative that painted a very negative picture of male gamers indiscriminately as racist, sexist and homophobic.
But as you said before nothing in existence is free of bias so why call me out when I said Wikipedia is not a credible source of information in case of anything that can have poliarized viewpoints.