In sociology and gender studies, homosociality is a term used to describe the prevalence of non-romantic, non-sexual same-sex relationships in human societies. Empirical studies have demonstrated that the homosocial relationship is the dominant relationship type among nearly all human societies.
In other words, most people on Earth prefer to spend most of their non-sexual, non-romantic time with people of the same gender. So it's kind of an obvious point.
The term homosocial was first widely popularized by queer studies scholar Eve Sedgwick in her writings on "male homosocial desire" in the 1980s, although the term was used earlier by others in various contexts.