There's a theory going on that a Gem's place in gem society is determined by Moh's Hardness scale; basically on scale of 1-10, Pearls are on about 2,5 while Diamonds are on 10. Ruby and Sapphire however are on 9, directly below the Diamonds, but by fusing and becoming Garnet, it all falls down the scale somewhere along the Quartz's and Peridot, about 6-7.



They may have become stronger, but they chose to become something less in the process, which would earn them the ire of White and Blue Diamond, if me make the connection that they're their "childern" (not blood related childern, since we know how Gems are made, but more like Gems made in their image and possessing a certain merit of their powers).