I'm not sure if the average person has the patience to sit through an entire movie anymore either, and not just in the US. Smartphones and social media have shortened our attention spans by making us crave for quick dopamine hits. I used to be able to watch an entire movie uninterrupted, whereas now if the movie is not engaging, I tend to reach for my phone.
Music enjoyment has also taken a back seat, and I usually put it on in the background while I'm focusing on something else, instead of actively listening to it. I think the shift from music being released as part of thematic albums on physical media to individual tracks on online services is part of the reason for this. The average music listener just hits shuffle on a random playlist rather than focusing on a specific band, album or even genre.