What the article seems to notice is that some parts of a civilization succeed to institutionalize themselves (and gain momentum over others thanks to it) and some don't.

In a very sketchy way:

- you may have excellent scientists and prestige for science, but no institutional structure/ecosystem to support, promote and benefit from it;

- you may have lousy clergy but a well-working institution/structure of religion that helps with its prominence over society.

(and the other way around, and mid-ways as well)

He's responding to a comment, which is about the situation now.