[dreamcompiler]

Yes and no.

Yes because the web is already a kind of knowledge graph but it's mostly written in natural language, and thus it's very hard for machines to traverse and reason about it. The Semantic Web was an attempt to formalize some ways to make the web's inherent knowledge graph nature more explicit and thus easier for programs to understand.

No, because knowledge graphs predated the web by many years and KGs are a bigger topic than just the web.