We don't have this problem in Australia, where a sandwich is narrowly understood as being between two slices of bread cut from a loaf.
If it's on a bread roll it's not a sandwich it's a roll. If it's on a burger bun it's not a sandwich it's a burger. A sub is not a sandwich, it's a sub. A hot dog cannot be considered a sandwich, nor could a cake or anything else that's clearly not a sandwich.
Does this mean that since Denisovans still lack a proper scientific name, they are now going to be homo longi?