Every professor of literature I have ever met would support this quote. To write anything well, you must read much and live deeply. All poetry, song-writing, essay-writing, written response of any kind is a deep, visceral reaction to our surroundings and our lives. We are in love, envious, greedy, angry, passionate, sorrowful, sympathetic, logical, emotional...whatever one is experiencing at the time will color the response and the writing. Personal experience and expertise just enhance that reaction.
The introduction to Thomas Foster's How to Read Literature Like a Professor and How to Read Novels Like a Professor echo my response.
I have included one source below...Mark Edmundson...whose entire book Why Read? explains why we do and why we should read actively throughout our lives.
Hope this helps! Good luck!