It was a latent feature in FTL 1.5.13 that some modders had discovered and used.
Comment: "Arsenal+ English Translation" Mod
mr_easy_money wrote:in FTL 1.6 you can no longer put the name of a random crewmember in event text via "%req"... all places where that happens now look odd because of that.
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Arsenal+ makes heavy use of this.
You don't need to reinstate the feature, but if the file is cruft, is should be removed - both for tidiness and to avoid misleading examples for mods.
Article: The Cutting Room Floor Wiki - FTL Test Events
The entire file 'nameEvents.xml', containing six unique events, is unused, and appears to be an experiment with using the names of crew members in events. The specific syntax used in the file seems to differ in many places from the syntax used in other events, implying that this file is relatively old. More than one of these events refer to the player ship as "the Kestrel" by name, implying that these events were written before the other playable ships were added to the game.