People have short attention spans. Theaters had to post warnings for the last Star Wars film that it had several intentional seconds of silence, because people thought the movie must be broken[0].
I saw that warning in the projectionist area, so projectionists didn't think the system was malfunctioning, phrased similarly to the one in that article. I wonder if those theatres just put the sign in the wrong place, or thought it was supposed to be public when it wasn't.
Crews-Offerman in 2020, with Offerman spearheading a War on Boredom that is just him insisting everybody should grow the fuck up and be able to sit quietly for at least 10 seconds at a time.