You're right to doubt about this. Normal wallpaper cannot. But acoustic wallpaper is not ''just'' wallpaper. It is made out of recycled felt, instead of paper.
It is a lot thicker than average wallpaper. Compared to normal wallpaper it's about 20 times as thick (6mm). When soundswave hit the wallpaper, they will be absorbed into the material.
Even more than wallpaper, it looks like a very luxurious walldecoration once installed. And is very soft to touch.