Exactly what it says on the tin. Can somebody please explain this to me?
The name Diamond Authority comes from a conspiracy theory that Ronaldo formulates at the end of Keep Beach City Weird. He mentions "polymorphic sentient rocks", says its part of the "great diamond authority" and says thery want "to hallow out the earth". Becuase polymorphic sentient rocks is a pretty accurate discription of Gems a lot of people assume that this particular conspiracy theory might be foreshadowing something; perhaps the cluster, or the reactivation of kindergarten? The truth is we don't know.
Diamond Authority theory claims to already know that the Diamond Authority is and who the rulers of Home World are. There's a logo found repeatedly in the Sky arena in "Sworn to the Sword" of a diamond made up of 4 smaller different colored diamonds "white, yellow, blue, and pink". The DA theory asserts that rach of the colored diamonds represents a leader of Home World.
The Pink Diamond theory requires you to presuppose that the Diamond Authority theory is true then goes onto claim that the Pink Diamond is Rose Quartz. On Jasper and Peridot's ship there's a similar logo of a triangle and it has three smaller colored triangle inside of it. "blue, yellow, and white", the pink is missing.
Making Rose Quartz a Pink Diamond would just be a retcon and an unessesary one at that. There's no reason storyline wise or character wise for us to assume this is true. The fact that Peridot was able to recognize Steven as a type of Quartz instead of a Diamond takes some credibility away from that theory, also Rose Quartz doesn't have a similar design to the only other known diamond, Yellow Diamond.
The Diamond Authority theory is a huge assumption based on almost no evidence and the Pink Diamond theory is a smaller assumption built on that huge assumption. Can somebody please explain to me why this is so popular?