It is true that on Twitch, when a popular game has drops, the viewer numbers go through the roof. But I don't think you can extrapolate that an unpopular platform could pull viewers away from Twitch by having a bunch of unpopular streamers do drops. You'd probably influence which streamers on Mixer got viewers on Mixer, but would it get people to drop Twitch? I strongly doubt it.
More to the point, no other platform has succeeded here either. Whatever that Facebook streaming thing is is a non-factor, YouTube streams exist but seem to be used primarily as a way for YouTubers to do events rather than a real Twitch competitor, etc. I'm not sure a Twitch competitor can be viable until Twitch does something to drive people away. The network effect is strong.
More to the point, no other platform has succeeded here either. Whatever that Facebook streaming thing is is a non-factor, YouTube streams exist but seem to be used primarily as a way for YouTubers to do events rather than a real Twitch competitor, etc. I'm not sure a Twitch competitor can be viable until Twitch does something to drive people away. The network effect is strong.