The first thing to notice is that despite what most gamers think, there are indeed Gorons in The Wind Waker. These gorons were well-hidden by the developers; they take the guise of the three merchants involved in the trading quest in The Wind Waker. These three merchants are placed on separate islands and can only be unmasked if you use the deku leaf to momentarily blow their hats away. Aside from that, there is a pattern on their backpacks that contains the crest of the goron tribe from Ocarina of Time, denoting them as being connected with the same Gorons from that game. However, This is all of the information we can gather on the three merchants, and it leaves a lot of room for speculation.
One possibility for the mass disappearance of the gorons is the idea that they were only recently wiped out on the destruction of greatfish island. Since the inhabitants of the island are never revealed, we are only left to speculate on who lived on the island prior to its destruction. However, after the island is destroyed, the remains have a sole inhabitant; a goron merchant that resides on the beach. It is very possible that this place holds sentimental value to him, since there is no logic in a merchant residing on an island that the rito postman believes to be cursed, not to mention the fact that the ghost ship occasionally makes its rounds there. therefore, it is possible that the island is at least significant to the gorons, and cold quite possibly have been there home.
Another possible explanation for the scarcity of gorons is an unmentioned event that caused them to fall out of favor with the other species. While no event is specifically alluded to, there are hundreds of years between Ocarina of Time and The Wind Waker that could be made into a game at a later date. Such an event would explain why the gorons are trying to disguise themselves to travelers, and why they are scattered across the ocean rather than living in one place. There is certainly a possibility that the gorons fear retribution for an event in their past, and therefore disguise and scatter themselves to avoid extinction.
That's pretty much all I have to say about that. You guys can respond to my theories or make your own if you want. I appreciate any feedback you guys have.
