Captain Birdseye: "if the definition of a traditional singer is one who learns songs orally ,from a community,then that makes anybody a traditional singer who learns traditional songs, orally from you tube ."

What an interesting point Cap'n...
Not one that I have an opinion on, but I'd be curious to hear other's responses to that idea.

Azizi: "I believe that some songs are likely to be performed more authentically (which is to say the way its composer/s wrote them to be performed) if they are sung by an individual from the same population as the composer or by a group that is comprised of (or mostly comprised of) people from the same population as the songs composer/s. For example, I would much prefer to hear a Black gospel song sung by a Black choir (in a "non-concert style") rather than a White choir singing that song."

Your feeling that a song aught to ideally remain sung within the context of the source of that song, raises some quite curious questions for me. You speak of 'population' in your first statement, then by example cite prefering to hear gospel sung by a 'Black choir' than a 'White choir'. In this instance, you are singling out 'race' as the definitive 'population', but imagine say a non-religious London Black youth choir, would that 'Black choir' be acceptable? Or would the absence of the initial religious and National human context (or 'population') make this Black choirs singing less appropriate. Also compare a white Christian American choirs singing of gospel to the non-religious British Black choir? Who's singing of gospel would be more 'authentic'?

I'm not trying to be awkward or contrary btw. I'm just curious about your thoughts. Especially as if one were to extrapolate from your statement, then one might say that a singer of Traditional English songs, who comes from a comfortable Middle-class background, aught not to sing songs that arose from tough Working-class industrial sources and so forth.
Where does one draw the line? And what are the demarcation points?