I think its literally just trial and error for news companies to see what can enrage people to create an outcry, then make it as extreme as possible. If it works do it again, if not move on.

Also playing the identity politics with finding one off fringe cases, calling it systematic and talking to "experts" to make it sound believeable. Then cherry pick stats, twist their meaning and blow it out of proportion.

I think thats why we see surges of the same type of news at a time. I remember seeing a bunch of articles about pick up trucks being bad for the environment like 6 months ago and it was everywhere for 3 weeks, and people rallied behind it.

After that I think it was the housing market, then airlines being bad, and so on.