The article mentions South Park too. I once loved the show, and still remember many moments in a strangely fond way. But the problem of Poe's law and the like means satire is sometimes taken seriously, and the cumulative effects of that have serious and real repercussions.
The creators of South Park, for example, recently "apologized" to Al Gore[1], who they ridiculed mercilessly. Many people believe that ridicule seriously hurt the climate change movement. I can't imagine what a real world solution would look like, but I would gladly live in a world where those episodes disappeared and we were in a little better spot regarding climate change.
We probably don't yet know what the lasting legacy of PewDiePie will be, but personally I'm doubting the positive aspects of it will outweigh the effects of many of his viewers taking some of his satire seriously.
[1] https://www.salon.com/2018/11/08/south-park-apologizes-to-al...