Very interesting topic, as an Argentine myself I would say that generally when we say negro we don't really talk about the racial group that is so stigmatized in America, I have blond friends that we always call negro in my town, I have never analyze so much the meaning of the word and a black person is the last thing that pass through my mind when I use that word, not the same happen when I hear that word in English as all the movies that come from America teach as that the word Black have a bad implication or a bad meaning, when I go to Europe or EEUU I know that i don't have to use them as the meaning and implications there are bad.
From my point of view and my cultural background I think is wrong to put a bad meaning in a word as if it would be bad to be black or to be Chinese that it cannot be named, why is that some words are not stigmatized and some other are? Is that is better to be called American than to be called black? The same ban on the word generates a bigger problem as it put some groups over other groups.
Example of this: call someone black when you don’t know his name is wrong but the same when you call someone Red hair is ok so what is the message here? That been black is bad and been red hair is cool????
That is my thinking; of course it can be different from the point of view of a porteño as I’m from a small town where racial difference means almost nothing. Still I will say that I think that Argentines are in lot of situation racist specially again certain groups of immigrants, I cannot measure if Argentines are more or less racist than Americans or European as for that I would need to understand much more the culture in there.
In any case you cannot use the same stick to measure a word or behavior in different country’s as the implications of that is not the same in different cultures.
Anyway as RichOne was calling my opinion from the beginning here it is
