The turkey is food but a necessity as that is how we can have a bonfire. The fire has to be put in a pit that is used for cooking. A code requirement.

Turkey is an authentic UK food.

Actually bonfire is a cobbled together tradition made from bits and pieces over the centuries. If people do not find it important for several reasons remove the one reason that retains them and it fails.
Too much emphasis on fireworks for example and not enough emphasis on the national values it represents. We always do a sermon and while digging the turkey up we tell the story of the plot. Keep all dimensions equally interesting and accessible.

Conrad