Catching up on this conversation, it strikes me that emacs seems especially prone to creating Borg-like systems that start focused, gain adherents, then expand to include all nearby territory, especially UI territory. I'm thinking of gnus, company/ivy/helm, and org (as well as some MIT-specific systems from my youth); I'm sure there are more.

Is this just another corollary of Greenspun's Tenth?

~Chad