This is a very interesting thread! If the original Link was black, then I wouldn't have problems. The only reason it bugs me because the traditional Link was "Hylian". We know this from OoT and Deku Tree's cut scene. I'm not sure if "Hyrule" has black people in it, but they could exist, and...
I don't think that's entirely true. I can recall at least one work of fiction where a man of African descent was present in Europe, and I'm sure there are more. It probably wasn't common however.
I don't think Nintendo would do this, simply because Link is a mascot for their company, and it'd...