Now, a lot of buzz about these other systems, particularly from 5E haters, makes it seem like D&D's bottom line is threatened. Though, im guessing its like World of Warcraft and every other MMO out there situation. Something would really need to take a nibble at D&D's bottom line to cause a hard reset reaction, and if PF2 cant do it, these other launches are not likley to either.
So, my current way of thinking is that, if everything is brought down to dollars and cents, and growth rates and all that jazz, people could make the argument that the 5e system could just keep on going until eventually sales start to flatten out for whatever reason they do. But I also know that not everyone, including decision makers, think rationally or agree what's rational. Or rather, if the growth rate is 12% (number pulled out of my behind), and new executive thinks the growth rate should be more like 20% (also a made up number), then you start hearing stuff like "Oh, dear, the brand is under-monetized". People make business decisions based for all sorts of reasons - "OMG, MMOs are going to kill our numbers" or "That's the last guy's project, I want to put my own stamp on things."