I've seen enough articles and questions like this online, but I do not buy the idea because it can never be accurate since you don't know the mind of everyone to warrant knowing their plans towards Bitcoin.

Bitcoin can't just be averagely divided by the world's population without knowing the true intention of people. What if, in the forever future, Bitcoin adoption will not be more than 20% of the world's population? Also, among these people, it is not everyone who will be willing to deal with Bitcoin every time, not to mention owning it. This makes it incalculable in my opinion.