Same as pool in general, a new business model is absolutely necessary for the sustainability of streamers, otherwise they too will perish along with the game itself.
Promotion is crucial, and at this point it's all our responsibility to give this back to the game, that give us so much pleasure and satisfaction. We all must be ambassadors if we expect this to stick around. Should all of us simply take and never give back, then there will be eventually be nothing left for anyone.
The commenter that mentioned bringing someone new to the game at least every now and then is definitely thinking right.