Well, yeah, of course if you're just sitting in your living room you'd rather read than listen; however that's not really the use case of a Podcast.
The value podcasts bring is you can consume them during times you can't read. During exercise, driving, walking to work, cleaning the house, cooking, and train/car rides (for people who get motion sick while reading in a moving vehicle). They turn tedious menial tasks into times when you're mildly entertained - that provides immense value.
They can also be used for a slightly more interesting white noise.
The value podcasts bring is you can consume them during times you can't read. During exercise, driving, walking to work, cleaning the house, cooking, and train/car rides (for people who get motion sick while reading in a moving vehicle). They turn tedious menial tasks into times when you're mildly entertained - that provides immense value.
They can also be used for a slightly more interesting white noise.