Like any other theory, String Theory is just an abstraction that allow us to explain our observations of the real world.
Newton´s mechanic is not real, Einstein´s relativity is not real nor also the Standart Model, They are just interpretations of the real world that allow us to explain it and make predictions.
Stephen Hawking agreed with the topic of String Theory. We clearly know that he was a very intelligent man and a reliable source of information. He deeply believed in String Theory, I do understand that I should not believe solely in one man. This would make me a Totalitarian, But we cannot disregard relevant opinions from reliable sources.