Man, if you haven't, read the book Sapiens. (I just read a fat chunk of it the other day.) It's only mildly biological and had some fun philosophical hypotheses. One of which stated that the power of humans is that we are able to come up with powerful fictions. Money, government, religion, and the like. The importance of this was connecting multiple people together.
The fictions that connect us are plentiful indeed - even at the personal level we tell ourselves stories to keep us going, to keep us connected. The challenge comes when we keep a story alive and act on it, even though it is doing us harm.
For sure. The intersubjectivity of belief in fictitious stories are far too large for one person to change. It's crazy to believe that people aren't much different than our ape cousins in small numbers, but there's almost an exponential effect when we congregate. Crazier to think that what makes us "special" are delusions.