Magical powers
As you know, Nietzsche is no fan of socialism. I only consider what Nietzsche previously wrote of socialists and assume it in this aphorism. He mentions “socialists and state-idolaters” in the same book, but it goes further back, for instance, in Human All Too Human. Their desire for state power is unavoidable.
Maybe I’m wrong but my reading is that Nietzsche was psychoanalyzing the socialist, criticizing how he dehumanizes the employer. The employer is unknown and uninteresting. At the same time he is a cunning, blood-sucking dog of a man, while everything else about him—his name, shape, manner, reputation—no socialist cares about. In my mind this is dehumanization.
But, in an extra little slight upon the socialist, following a tyrant into tyranny isn’t as painful, and if “the nobility of birth showed in [the employer’s] eyes and gestures, there might not be any socialism of the masses.” Perhaps this is why, historically, socialists have followed tyrants and demagogues.
As for capitalism, there is no system that does not consider the management and segregation of capital. In that sense, all economic systems are invariably capitalist, socialist or otherwise, the only difference in being who controls it, private or the State. Had socialists named it something else, like the Monopolist system, we might well have been passed it by now.
I'm not sure how this fits into your thread, but if I have strayed too far, I apologize.