Author's place in his creation

“The author is a prism which his audience can look through at thy life phenomena, characters and situations from a new angle,” - I heard this once at VGIK (Russian State University of Cinematography). That's when I thought: it turns out that the author must - first of all - consider and feel these very phenomena, characters and situations.

Stories made entirely with bare imagination are boring graphomania 99.9% times. Even the most fanciful sci-fi or fantasy are based primarily on one's own experience. So how to gain this very experience? Sitting at home writing? I doubt this. There are yet books, articles, movies... But that's someone else's creativity. Experiencing someone else's experience, so to speak isn't a way to build your own - absolute unique exp!
It turns out getting into stories and jumping head-first into curious situations is The sacred duty of any author who tries to find his own style, his own voice! At least that's my POV. Do you agree? Or do you have any examples to show me opposite way to build a unique author's way?