To be a great storyteller, you need to be detached. The trick is that you have to be detached without being dispassionate.
You have to be detached enough from the world around you to see everything as new and fresh. You’ll never be able to see the potential for a story in something if it doesn’t surprise you. Having said that, you also need to be passionate enough to turn it into a story and share your surprise with everyone else.
Of course, detachment and passion aren’t enough by themselves. You need to be superb in your medium of expression too- whether it’s the written word, or photography, or cinema, or music. But technique can be learnt with practice. Detachment and passion won’t come unless your personality is built that way.