This subject has been flogged to death many times in the past, so I suppose it had to appear here.
The Yellow = everyone claim: Well, no, to be blunt. There's a certain amount of sticking one's head in the sand to claim that yellow is fine because no one is bright yellow, so yellow must equal everyone. Most people of european descent key on the color (yellow) and ignore the value (used in the artist's sense meaning relative light and dark). You will find blacks will key on the "paleness" and while most look beyond it, are not entirely happy with it. The counter is, "It's a toy for heaven's sake." Well, Lego itself has broken that mold with other products, so the real issue is tradition, and I must admit I kinda like the ranks and ranks of yellow headed sappy smile soldiers I have. But I don't think of them as representing native sub-saharan africans.
The Real People Dilemma: If yellow equals a generic everyone (which I don't believe Lego claims - they just clam up and hope no one notices the Emperor is prancing down the promanade bare naked), then what about specific people? Star Wars opened a new can of worms. Don't believe me about the "paleness" of yellow? I (and many others) called Lego's bluff many times in challenging them to produce a yellow Lando. They didn't. In fact, they avoided making him for a long time. Clearly Lego disagreed with the "Yellow = Everyone" argument. But they were trapped by their decision to make everone else yellow, so there they sat for a long time hoping no one would notice that they were avoiding making Lando and Mace. But that lead to another problem - why isn't Lego making the two major black characters from Star Wars? Because of racial issues and no other (don't confuse "racial" with "racist")! Oops! Horns of a dilemma! They finally bit the bullet and made Lando in brown, but now that makes their decision to make everyone else as yellow look silly. There was no winning decision except to have stepped into the 21st century with a more updated policy in the first place. They gave in with the NBA, but you'll also notice that the non-specific figs are good old bright yellow.
Me? I kinda like the silly sappy smile and yellow countenance, but I also wouldn't mind some variety. I add "diversity" to racial, not "problems".