It draws a contrast with the West, which it says prefers smaller clubs (like the g7).
Even the industrial revolution of the late 1700s, which many people believe was the result of the invention of the spinning jenny, was actually caused by all sorts of factors coming together: increasing use of coal, firmer property rights, the emergence of a scientific ethos and much more besides.
Does "it says" and "people believe" function as parenthetical phrase? If so, the object of "says" or "believe" should be "which", but "which" refers to "the West" or "the industrial revolution". Actually, it says "the West prefers smaller clubs (like the g7)", and so does "people believe ".
Is the first equal to "It draws a contrast with the West, which prefers smaller clubs (like the g7)-it says"? And then the object of "says" becomes "which prefers smaller clubs (like the g7)".