I get you and normally wouldn't either. I was a little impressed when I could switch to like 10 diff languages on the fly. As a foreign language learner seems like it could be pretty helpful.
It's probably most useful for utility or news content. Not 'high effort videos' about an interesting topic. I'm imagining you find a video in another language that fixes a problem you have and can switch to your language to watch.
I sometime watch videos in English with the automatic subtitles. Sometimes I can't understand a few words and the subtitles help me. Most of the time I watch them without subtitles, and rewind the video a few seconds to rewatch a short part with the subtitles enabled.
