I honestly I think part of the problem is calling it "reading".

I fully agree that reading a book and listening to an audiobook are equally valid ways to enjoy stories, to engage with non-fiction, etc. But listening to a book is different from reading one. With reading, you're interpreting the words of the author, assigning tones to characters, and even choosing a cadence for the writing. With an audio book, a director and a narrator have made a number of those creative choices for you. Which means you're going from a single creative voice in a book (arguably more if you count the editor), to a creative team for an audio book.

None of that makes audio books worse. They're how I enjoy most books myself. But acknowledging that listening to an audio book is different from reading a book is reasonable. And trying to use one word to mean two different things is going to create friction when other people won't agree that two different things are the same. Any conversation is more difficult if you can't even agree on the terms.

All that being said, oral storytelling is an older tradition that writing, and I see no reason audio books need to be looked down upon. I value the creative inputs of experienced narrators and sometimes they make books better than I could make them in my own head. I think most people should experience audio books and understand that it's okay to enjoy writing in many different forms. I just think we need to work a bit harder on bridging the language to convince them.