Why now? What's new?
I'm not certain that there is more emphasis on brand story telling, but it certainly is becoming more important. Consumer attention spans seem to be getting shorter, so you must engage prospects with a message that will be "sticky". This helps them position your product or service, and provides a context for its attributes that they can recall when it comes time to make a purchase choice.
Brand loyalty with consumers is waning. Storytelling allows marketers to convey the personality of the brand by conveying messaging that hits consumers' "emotional quotient". Ted Rubin calls this ROR or "Return on Relationship". The more intimate the relationship with consumers, the higher likelihood of resonance with intent. Check out the LinkedIn study on storytelling here: https://bit.ly/2wZhEh0.