Final answer:
Attitudes and engagement unify otaku culture, regardless of its content and genres.
Step-by-step explanation:
What unifies otaku culture as a whole is less its content and genres and more its attitudes and mode of engagement.
Attitudes within otaku culture can include a passion for anime, manga, and Japanese pop culture, as well as a strong sense of community and acceptance. The mode of engagement refers to how otaku interact with and consume their favorite media, such as through cosplay, attending conventions, and engaging in online communities.