Last year I would larp as a Spanish-speaking gaming streamer on Youtube to practice Spanish, talking out loud while trying some new game to force myself to speak it.

If I were trying to do that in private, I would stop after two minutes.

But the mere threat of someone watching me forced me to take it seriously even though I knew nobody would.

It was so effective that I would default to Spanish for the rest of the day, or I'd listen to Spanish and then realize how I could have communicated certain things better instead of just passively ingest it.

Though the same reason it was so effective also created a mental toll that I started avoiding by not doing it at all. Need to start it back up.

That said, I reckon the vast majority of streamers are gamers who do want viewership and aren't using it as some productivity hack.