In both Ocarina of Time, Nintendo shows us where the green tunic worn by all future Links comes from in the first place. The Minish Cap explains the origin of the hat piece of this outfit; however, that Link is already wearing the tunic that a future Link is supposed to introduce. Does this debunk the Kokiri as the origin of the outfit, or is there some other explanation?
No. The tunic in MC had no significance. The hat was simply said to "suit Link" at the end of the game. This was obviously to signify that Link has always fit the look of the green tunic and hat. I see it as more of something that the developers wanted to add to make this reference, rather than actually set up some kind of important event chain for the games.
OoT's tunic and hat has a little more significance, as it has been referenced in multiple games thus far. I highly doubt the Kokiri based their clothing off of the hero from MC. It was simply what they wore. They were an elf-like group of beings, so they wore what we usually see from an elf. Link's attire was based off of what the Kokiri wore in OoT, because he grew up alongside them.
Now in WW, as well as TP, the "Hero's Clothes" were based off of the look of the hero in OoT. WW makes it clear that the attire is based off of the Hero of Time's look. TP sort of makes the same reference, but because of timeline restraints, this is a bit debatable. However, I like to think that young Link himself was somewhat of a hero. I also like to think that the Spirits in TP that give Link his clothing knew of young Link in OoT travelling through time, and fullfilling his destiny as a hero there as well as during his childhood.
The other games, such as ALttP/LA, LoZ/AoL, and the Oracle titles, never gave any explanation to Link's clothing, as obviously it wasn't really a big deal then. That is simply what Link looked like, and fans were used to it. LoZ/AoL were the same Link, so of course they are going to wear roughly the same outfit. ALttP Link was based off of the original LoZ Link's look, but seeing as how I believe that game is a prequel to the originals, there is not definite, or storyline-based explanation, as to why he looks the way he does in that game. He just does.
Therefore, MC's outfit doesn't do much towards setting up a general look for Link. Although I believe it is the first game, it doesn't mean that all other looks for Link were based off of that. As you can see, OoT's look had much more significance on the history of how the hero in each game should look.
