Diversity can only improve a system. The article specifically addresses that point.
There have been books written on why nationalized heathcare is hard to achieve in the US. It's a very complex issue that is inherently entangled with both the mechanics of the US political system and the US media. Blaming it on a "diversity of viewpoints" does a disservice to the issue.
Once again, those Wikipedia articles are highly recommended reading.
The main example I pointed out is American politics. There is quite a bit of diversity of opinion and that makes it far more difficult to reach a consensus about a particular issue than you'll find in e.g., European and Asian countries, which have far more homogeneous populations (and by extension, far more homogeneous political/social opinion). As a result, the speed with which progressive policies can be implemented in America ...lags... our European brethren, to put it lightly.
I pointed out that you were talking like a Nazi because, in this instance, you were talking like a Nazi. Do I think you secretly harbor a desire to wipe out an ethnicity via genocide? Nope. Do I think that criticizing ethnic diversity as standing in the way of progress sounds suspiciously fascist? Why yes, yes I do!
Identity politics has no doubt hamstrung the American left, but that has had little to do with your cited example of the failure to implement a nationalized healthcare system. Diversity increases viewpoints, more viewpoints invite stronger debate. Does less debate lead to better outcomes, or faster outcomes? Which is preferable?
Believe it or not, I'm open to being convinced. Care to share what you're basing this statement on?
Why diversity is important to Hacker School
There are many reasons why diversity is valuable, but there are two reasons why it is especially important to Hacker School as an organization.
The first is that diversity helps to reduces the harmful effects of stereotype threat. Put another way, we focus on diversity so Hacker Schoolers don’t have to. We want you to be able to focus on becoming a better programmer, not being the only person like you in the room. The more diverse Hacker School is, the easier it is for a greater range of people to do that.
Second, a large part of the value of Hacker School is what Hacker Schoolers learn from each other. Hacker School relies on a diverse range of experiences and perspectives; if everyone were the same, no one would have anything to learn from each other! Our self-directed and peer-driven educational model is in this way very different from traditional, one-size-fits-all approaches to education.[1]
Given this, it’s unsurprising that Hacker School has gotten better as our community has grown to include more women, trans people, genderqueer people, older people, younger people, parents, and people from a greater range of racial, ethnic, and socioeconomic backgrounds.
[1] Consider a traditional lecture-based class with a fixed curriculum. That model is built around homogenity, not diversity: It’s much easier to operate if everyone involved has the same background, interests, learning-style, and rate of growth. Our model is the opposite: It’s helped not harmed by diversity.