Thanks, this is what I'm really trying to explore here. I think there's a difference between Eminem's path to glory and his experience with racism compared to these two and the overall response from the black community.
Like Trey said there's likely an issue with race here but I feel like there's more to it. It's like the biggest setback for Iggy and Macklemore is that what they're doing has either already been done by a black person (explains the comparison to Nicki) but conveniently ignored, or their reputation is underwhelming compared to someone else but they're somehow better because they're white.
Compare these two with say... Robin Thicke and there's quite a difference. Robin Thicke is a lot like Teena because they're very talented and have been in the industry with other prominent faces long enough to be welcomed. And yeah, demographics are also a factor over the years.
But here we have these two, who like you, I believe their actual talents are being overshadowed by their appeal because of their race.
I think this isn't necessarily racism entirely from the black community towards them because they're white artists, this seems different from what occurred with Eminem. However, there is a race issue in play, no doubt about it.
I think this is the community going on the defensive because music we've identified with and nurtured is somehow only valuable when it's on white person than a black one and that's the problem, that's the real issue.