I have talked to my sleep psychologist (a PhD) whom I see infrequently. She is a skeptic and very science-based. She said that she was skeptical about the idea that audiobooks are not as good for us. There simply has not been as nearly as much research into audiobooks, but as a largely unstudied medium, they are not necessarily worse. And she and I talked about how some narrators are so amazing that your mind works at high speed imagining everything that is happening in the book, even more so than you imagine when you read. And imagination can't be a bad thing, right?
Still, I have finally started reading a paper book and I am enjoying it for a change. I have not a read a real thick book in years. It is a non-fiction book, but still.