I assume you mean the "ze" part? If so, no, that's one of a series of new pronouns that were coined specifically to be gender neutral.

https://www.mypronouns.org/ze-hir

Ah yes, that was the part throwing me.

Seems unnecessary when the original quote was already gender neutral with the use of they, an actual pronoun already in common use?

I wasn't looking at the original quote when I wrote what I wrote above, FWIW. And I wanted to avoid the instinctive inclination to write "he", so I went with "ze" because using "they" for singular case always feels forced and awkward to me. But yes, that would have been fine as well. It was a choice I made at a moment in time, not something that I spent a lot of time analyzing and debating. :-)