Same here. I still prefer single narrator. There are a few cases when there are just too many characters but it’s still much easier to listen to than multiple narrators.
I have also noticed sound effects in audiobooks. I like it at the end/start of a chapter, but it need to be subtle. I listened to Fractal Noise, which has audio effect for the thumbing sound, very quiet at the beginning but turned very loud at the end of the book. While it’s new and interesting at the beginning, I quickly grew tired of it. I’d rather only the narrator reading the book than hearing the sound effect.
I think it’s a matter of imagination. Reading/listening for me is not only about the story but also about my imagination. The sound effects removes this, sadly, despite the huge effort by the team.