There are too much information these days. We literally don't have enough time to fact-check everything and therefor we pick the most believable version of a story and with that new info we shape our future selves.

"But you don't have to pick a side, just ignore this information altogether." For most minor info this strategy works, but when the same piece of info appears repetitively over and over again you start to believe it subconsciously or it moves from "minor" to "major/important info" group which we can't simply ignore.