Do you have a study or article that references those findings? I’m just curious, since I’ve learned some Japanese and the most complex thing I’ve encountered while reading is not knowing certain kanji.
You might be able to get audiobooks through your local library and through an app called Libby! I love using it since I can’t afford a monthly audiobook subscription, and I struggle to buy things without knowing if I’ll like it or not.
Also, a great alternative to Audible is Libro.FM. It functions the same way, and you can set it up to support your local bookstore.