When I first downloaded 1.16, the texture was fine. However, after a short time the texture turned into the purple and black square that indicates a missing texture. I'm not sure exactly what caused it, so I'll just explain what happened right before the issue occurred.

    I had just died in a End City in my survival world and was going back to get my stuff. When I arrived in the end, I went through a portal that leads to the End Outskirts and died to some endermen. Frustrated that I died a second time, I closed the world from the death screen almost immediately without letting it load. This might be what caused it. After a short break I got back on and when I looked in a Chest all my bows had a missing texture.

     I would provide a image of the bows with missing textures, but I relogged and all of the bows I looked at turned back to normal.

If it helps, every one of the bows were enchanted and every one of them had taken some durability. I don't think any other item had a missing texture, but I closed the game as soon as I saw them, so i'm not sure. I've also tried to recreate the glitch to no avail.