Not true.
You add enough moisture to the stuffing to prevent dryness from happening. If your bird dries out, it’s because you didn’t make your stuffing correctly. You moisten the stuffing to just before being a sloppy soup, bit it still holds together. Also use egg in your recipe as it contributes to the moisture, and helps hold the final product together.
If you do this, even of the bird was slightly dehydrated before slaughter, and sometimes they are...you will be putting moisture back into the bird as it cooks, as well as the flavors of the seasoning from the stuffing.
Also, if your bird is dry and your stuffing was the correct moisture, it’s because you over cooked the bird. Dry tirkey is due to chef’s error.
If you are using a bread stuffing there is no way to moisturize it enough. Not even if it is soup.
Bread attracts moisture.