Five of Neil Gaiman's ten nearest neighbors by audience similarity are comedians, and not one is a fellow author. Similarity here measures how closely two entities' audiences resemble each other in composition — a score near 0.95 across the board signals a tight, undifferentiated cluster rather than any single dominant pull.
The shape is flat: scores run from 0.9449 (Patton Oswalt) to 0.9568 (Last Week Tonight), a spread of barely 0.012. The comedian subcategory dominates — Marc Maron (0.9537), Andy Richter (0.9527), Michael Ian Black (0.9519), and Jemaine Clement (0.9518) all cluster within a point of each other. Two actors round out the mix: Kristen Schaal (0.9522) and Kumail Nanjiani (0.9466), both of whom have strong comedy-adjacent profiles by subcategory. Last Week Tonight (0.9568), a TV show, sits at the top of the range but only barely clears the pack. WTF with Marc Maron (0.9536) adds a podcast to the mix, and Neil deGrasse Tyson (0.9489) is the lone academic in the set.
No other authors appear in the top 10. The audience that follows Neil Gaiman on social platforms looks, structurally, like the audience for a particular strain of comedy and late-night media — not like the readership of comparable literary figures.