I think the "gatekeeping" exists around what I think is an objective truth: you don't absorb and comprehend a book as well if it's a secondary activity to something else. It turns "reading" into having the news on in the background while you cook in the kitchen. Maybe you have a general idea of what's going on in the world - but you don't have an in-depth view of it.
Is it better than never watching the news at all? I guess. Maybe with news you can get away with it...but with a book, it's all about the immersion itself. I don't know how it could be a satisfying "read" to listen to an audiobook and only have a shallow surface level understanding of it, because something else also held your attention at the time.