>>41579604Japanese copyright law has no fair use exceptions that allow game streaming: a company big enough to be worth suing would be cautious enough to get prior written permission for any of their talents to stream a game.
Technically, even the US is on thin ice there. It's really kind of still up in the air whether Let's Plays counted as a transformative use, but nobody ever went nuclear, not even Nintendo.
That's before you get to performance and sync licences for any of the music in a game.
So, they're just being as careful as they probably should be.
