What Young is doing is not "violent" nor "terrorism". I think you know what those words really mean.
The principle of "don't negotiate with terrorists" is applicable far beyond literal terrorism and I think it's exactly the moral calculus necessary for Spotify to reach the conclusion they did. Network members who think they can yield violent ultimatums to control the administrating entity are toxic to all of their peers.
I agree with you that it's not terrorism, however.