If the 3 are associated, thus inclined to push their narrative it doesn't change much that there are 3 of them, I'd say.
I only read the wiki article and it seems more plausible this (as most things?) was invented by countless little remixes.
Of course an "origin story" is also the more attractive narrative on the recieving side, since you know, people are used to and like stories with clear protagonists
Even though this is true for like 90% of my thinking (that I can see when I try), so far I'm concinced this ist because I am a predominantly language-and-normal-grammar-rules thinker.
There are people that mostly think via associations of words that don't have to be formulated/ cast into grammar.
And then there supposedly people mainly thinking in pictures or smth, without words.
Anyways for some people rubber duck mode reoresents a change in thinking method, I think