True, but just in case folks are thinking D&D never has, and for some reason couldnt/shouldnt, PF1 is the case study saying it can.
Counterpoint-
Achilles: Hey, Zeno, I have a great idea!
Zeno: .......
Achilles: ZENO! ZENO! ZENO! ZENO! ZENO! ZEN......
Zeno: What. What do you want this time?
Achilles: Okay, so here's the deal. You know, how, since the 70s, D&D has always had the three core books? For every edition? You know, the PHB, the DMG, and the MM? The holy trinity? The three sisters? The Athos, Porthos, and Aramis of rulebooks?
Zeno: Yep, I know.
Achilles: Well ... what if we just ... don't?
Zeno: I'm .... I'm not following you?
Achilles: Yes! Exactly! We're going GALAXY BRAINED on this, Zeno! Instead of selling three books with a rich history and name recognition, we will sell ... wait for it .... wait for it .... wait for it .... ONE BOOK! We can call it something evocative, like ... I dunno ...
D&D Core Rules.
Zeno: So your suggestion is to take three brands with almost 50 years of history and get rid of them. And to reduce the amazing sales of three books into one book?
Achilles: YES!
Zeno: But why?
Achilles: This is the prestige. Because ... other less successful games without the brand recognition do it!
Zeno: Okay. Um ... and how are we going to make up the lost sales from going from three well-known books to one book? Are we going to raise the price egregiously?
Achilles: Of course not! I don't have that step figured out yet, but .... I am sure that there is profit on the next step! GALAXY BRAINED!!!!!
Zeno: .........this is why I have your phone number blocked, Achilles.