It is an issue that is rather common to encounter is Dash**. The “standard” solution is to create one combined callback, which will typically require mixing the logic of otherwise unrelated functions along with not-so-nice dispatch logic (a lot of conditional statements based on inspection of which component triggered the callback).
As a concreate example, consider logging. Say that you have “create”, “save”, “update”, “load”, etc. buttons that perform separate actions, but all needs to write some logging information (e.g. if an error occurs) to the same output. With MultiplexerTransform you can create an a callback for each button with their respective logic. Without it, you would have to create one callback to handle all actions, which will become rather messy (: