The 'Noble Savage' myth is the last vestige of racism still taken seriously by educated Westerners. It seems harmless enough, because the stereotype is positive, but it's still an assumption about moral character based on race.
The problem with the Noble Savage myth is that it is a ridiculous romanticization, much akin to the myth of the "simple, merry country folk." The idea in itself doesn't have anything to do with the race of the savages in question.
