No one has time to research everything deeply for themselves. What the COVID example did for me was change my default assumption when ingesting "news" from mainstream sources from "probably true" to "probably bushit". If the thing is important to my own life, I'll look into it more deeply, if not, it stays in the " probably bullshit" category.
Once you change this default assumption/prior, it also flips the things you heard in the past to "probably bullshit", which you would have to research deeply to overcome if they are in fact true.