[okayishdefaults]

Consider the bbt as a collection of observations and models that are independently validated. As each of those components reach increasingly accurate representations of what we observe, the bbt improves.

In this way, there can be no alternative as there is no alternative to music theory. Some people may have a very narrow view of music theory, but it truly encompasses every model we accept about aspects of music.

Tldr- the questions can't be answered because the bbt is a not a theory like "THE theory of relativity". The "theory" is at the end of the term which denotes a collection and not a specific model.