The lead siblings, Cate Randa (played by Black actress Kiersey Clemons) and Kentaro Randa (played by Japanese actor Ren Watabe), represent a mixed-race family with a Japanese father, introducing incidental racial diversity that aligns with modern sensibilities without clashing against source material (as characters are largely original). A significant subplot involves Cate's lesbian romance with May, highlighted in LGBTQ+ media lists and sparking minor backlash from some viewers labeling it 'woke' or unnecessary.

Additional diversity includes Asian leads in key roles (Anna Sawai as Keiko, potential 1950s interracial undertones) and a varied ensemble. User reviews on Metacritic and forums note 'DEI hires' and 'forced woke elements' like dialogue, alongside complaints about human drama overshadowing monsters, but no creator activism, overt social justice lectures, or 'go woke go broke' collapse—the show was successful and renewed. These elements influence character arcs and subplots but remain secondary to the monster/family adventure narrative.