The scriptures are God-breathed but they are not “The Word of God”. The Word of God is Jesus. A person and not a book. The scriptures are about the Word of God (Jesus said so) but they are not Him.
Prove otherwise from the scriptures if you can.
Why do people refer to the Bible as the word of God? I don’t really know. It might be because people would prefer to read a book than rely on experiencing Jesus. A book is more controllable than a God 🙂