It's causing disenfranchised citizens to believe in a global conspiracy to subvert a man with a trail of failed businesses and marriages, as well as, dictatorial aspirations. It should be treated as a Hollywood recycled plot, but people are actually buying into it. Buildings burning will be the least of our problems if it continues to spread.
If the state establishes a habit of executing QAnon believers in the street, or using violence against them even when they're being peaceful, and the liberal president doesn't think it's a big deal, and liberal citizens think they deserve it, then it will be understandable for them to start burning things.