If that's all they wanted to achieve, then maybe they can pool that "demonetized" money and raffle it to the smaller musicians. If the outcome is only that Spotify stops paying out on something they used to pay for, by unilaterally changing the terms for the users without any bargaining power, then it feels like any effect other than increasing net profit is just the cherry on top.

You can't just say "in order to improve your experience we've decided to stop paying you" and expect people to trust your motives.