> Doesn't it mean that most of these videos are watched with subtitles?
No, it means they're not actually watched at all. Facebook autoplays videos (without sound) when you scroll through your timeline. If you get distracted and stop scrolling and 10 seconds play, they count that as a "play".
Doesn't it mean that most of these videos are watched with subtitles?
How is that taken into aaoumt with the "death" of text?