It is so strange that this article would hijack the term "rationalist" to mean this extraordinarily specific set of people "drawn together by AI researcher Eliezer Yudkowsky’s blog post series The Sequences, a set of essays about how to think more rationally".

As a counter example (with many many more people) is the Indian Rationalist Association (https://en.wikipedia.org/wiki/Indian_Rationalist_Association) to "promote scientific skepticism and critique supernatural claims". This isn't a cult of any kind, even if the members broadly agree about what it means to be rational with the set above.