It actually is just the slogan that drove away Art sponsors. How do i know? I had to deal with it all.
And actually yes at least 3 streams that started out as art streams only moved to only gaming.
As for showcased and thriving? Non gamer stream events who were told they would get front paged got bumped hours before an event cause games. Microsoft ruined Mixer for no reason not hard to see that.
Its this kind of disconnect from the community that allows you to just be like "I see non game content. Its everywhere" and no its not and if you do see it some one tooth and nailed to get onto the front page.