I don't think soft power necessarily have to positively influence others, it could also negatively influence others, the keyword here to influence others, bad or good.
I do think there are many kind of soft power. The US rely on hollywood, Japan on J-pop and Anime, Korean on Kpop and Kdrama. Germany has none of those and yet I would say Germany has tremendous soft power that attract people to Germany. Germany reputation is synonim with quality and hitech for a long time.
I think that Germany kind of softpower is what the author want China to emulate. Not something shallow like the hollywood or pop culture softpower.
Now whether I agree with the author or not, to be honest, I'm not so sure. I could see merits in his argument though.