First step was when internet went mainstream and news papers had to compete with news online. Things got a lot more attention grabbing. Or at least more articles got clickbaity. Then came from social media, who loved to use emotions to drive engagement so you got a lot of articles with emotional attention grabbing language. Meanwhile there is a large wave of consolidation where small media companies are bought up by bigger ones, usually with political leanings, that then start pushing a message, an ideology held by a small group. All together you now have a small group spouting their opining everywhere with very attention grabbing emotional laden headlines.