Historical factors have huge influences on the survival of languages. Take latin as an example. Latin was spoken all around the Roman Empire by hundreds of thousands of persons, and today it is considered a "dead language". No one speaks it, and only scholars study it. The fall of the Western Roman empire and the formation of distinct kingdoms over the ashes not only gave rise to Italian, French, Spanish, and "latin" languages, but also "killed" latin. This can be true for most cases. Imagine living in a country where only 1% of the population speaks your language. It will be easier for you to learn the more "popular" language, and your children will also learn it, eventually making it dissappear as the generations come and go. Other factors, such as political ones, can have an impact. Maybe the government does not want your language to survive, so they simply don't teach it at schools. In general, "popular" languages win over specific ones, even if the "popular" language is harder to learn.
So you’re saying there’s some sort of “evolutionary tree” for languages. Makes sense. But if a language evolved out of a different “tree” would that make it easier for some of those languages to survive (i.e. Chinese/Japanese)?