I disagree with the statement that they're "pretty inevitable" - why do you think that?

Its mostly based on intuition and pattern matching but to break it down as much as possible.

1) It seems like most movements of this very general type start collecting rituals at this stage.

2)My own personal introspection plus the feel of several recent conversations on LW meant that I (apparently correctly) felt that an event like this would gain widespread support if someone actually organized it.
In retrospect I should have put these down in prediction book awhile ago, but it slipped my mind.