Josh Groban's nearest audiences are comedians, actors, and TV personalities — not other musicians. Across the top 10 neighbors, only one shares his subcategory: Idina Menzel at 0.87, the lone fellow musician in the set.
The shape is flat: scores run from Patton Oswalt at 0.92 down to The Good Place at 0.89, a band of less than four points separating the top from the tenth. No single neighbor dominates. The composition of that band, however, is striking. Comedians account for two slots — Patton Oswalt (0.92) and Nick Kroll (0.89) — while actors fill five: Jason Segel (0.91), Zach Braff (0.90), Adam Scott (0.90), Kristin Chenoweth (0.90), and Patrick Stewart (0.89). Joel McHale (0.91) rounds out the set as a TV personality, alongside The Good Place as the one TV show. Idina Menzel is the only other musician in the top 10.
This is a cross-kind pattern: an audience shaped almost entirely by comedy-adjacent television and film, with the musician's own subcategory nearly absent from the nearest neighbors.