I think this is actually a large reason that the Baader-Meinhof phenomenon exists. In this framing of Baader-Meinhof, it is something that appears constantly,

I think this is actually a large reason that the Baader-Meinhof phenomenon exists. In this framing of Baader-Meinhof, it is something that appears constantly, but as it is to weird you ignore it. Then as you discover more things related to it, eventually it's close enough to your Overton window for you to be able to be ready for it. Then once you learn it you see it everywhere. It's interesting that you tie this with advertising, one of the things I learned watching The Social Dilemma was that the way that platforms like YouTube work is that they will attempt to funnel you into the most profitable content types. For instance if you are watching Gaming content on YouTube, it will recommend PewDiePie, a Gaming YouTuber well known to every once in a while say racist things. Then if you watch enough PewDiePie, you'll start seeing more racist channels. At some point you'll get Jordan Peterson(whom himself is mostly harmless...). If you watch one Peterson video your recommendations will flip from whatever you were doing previously to 80% his content, and if you continue down the rabbit hole it will get as bad as you can imagine. YouTube does this because the people susceptible to watch these videos are also susceptible to buy things from advertisements, so they are their most profitable customers. YouTube has unknowingly created a funnel that can move the Overton Window to turn people into extremists all so that they can make money from selling healing crystals to them.