Unfortunately finding a contrary result is a career limiting move. Consider Robert Putnam, who suppressed his research (showing that diversity harms social cohesion) for 6 years while trying to "develop proposals to compensate for the negative effects of diversity".
Here's the abstract from your link. A bit more complicated than your summary.
Ethnic diversity is increasing in most advanced countries, driven mostly by sharp increases in immigration. In the long run immigration and diversity are likely to have important cultural, economic, fiscal, and developmental benefits. In the short run, however, immigration and ethnic diversity tend to reduce social solidarity and social capital. New evidence from the US suggests that in ethnically diverse neighbourhoods residents of all races tend to ‘hunker down’. Trust (even of one's own race) is lower, altruism and community cooperation rarer, friends fewer. In the long run, however, successful immigrant societies have overcome such fragmentation by creating new, cross-cutting forms of social solidarity and more encompassing identities. Illustrations of becoming comfortable with diversity are drawn from the US military, religious institutions, and earlier waves of American immigration.
If you read the paper itself, it's basically empirical work describing the negative effects, followed by an essay claiming the positive ones. As I said - he spent 6 years looking for something to counter his empirical results, and published when he came up with it.
Note also that I'm not strongly endorsing this work - I'm just pointing out the strong desire to not publish a result against diversity.
I think it's obvious that diversity can be both good and bad.
A team where everyone speaks a different language is very diverse, but not effective, since there is no communication. One in which they at least share some common language which for all of them is a second language, not with full fluency, would be able to function, but likely not as efficiently as one in which everyone speaks the same language as their mother tongue.
And language can be just an analogy. Instead of language, imagine a cultural background of shared assumptions and experiences. A shared background can help avoid misunderstandings and speed up communication.
At the same time, it's clear that diversity can help in many ways, avoiding single-mindedness, for example. If everyone has the same concepts and background, they might miss something important.
For political reasons, people like to say that diversity is good, and it is indeed good in some ways. But that's far from the whole story.
It would be better to not use "diversity is good for business" as a slogan, when there are other more valid reasons to fix issues with inclusion where they exist.
It's hardly clear to me that ethnic diversity helps in any way for most companies. Several people at my current company told me they were excited that I'd be providing diversity. I asked them what they thought that would bring them, and after pressing the issue I realized they had no clue.
I have no clue either. Some unique perspectives I bring: I favor rigid APIs over close team communication, I favor Bayesian statistics over frequentist, and I'm working on convincing folks that the JVM is actually a great platform to deploy code on. Are these technical matters something that a certain ethnic group (different from mine) is uniquely single minded about?
I've been the bringer of diversity for most of my career. And I can't think of a time when it's actually mattered.
> JVM is actually a great platform to deploy code on
The JVM is a fantastic platform to build for and run on. I know of nothing else that's so powerfully general purpose for typical server-side business work, with such a compelling ecosystem. Multiplatform support can be useful, though mainly for me it's the ability to develop from any platform, rather than deploy to. It seems to be widely undervalued -- I would describe it as popularly unfashionable right now. Yet I don't know of any platforms with such deep ecosystems and comparable technical merit. .NET comes close (and is arguably better designed in some ways, and has some neat features), but is Windows-focused and seems to lack the open source communities Java has.
Talking about this almost makes me want to start a list of "awesome things about Java that are without parallel in other platforms".
I've enjoyed reading a number of the comments you've posted in recent days. Please continue and good luck with your evangelism!
I agree it might not help in all cases. But ethnic diversity can obviously help in marketing, assuming the target audience has multiple ethnicities, which is often the case. Aside from marketing, it might help less as you get more and more technical, but it might still help in areas in the "middle" like product design, etc.
Ethnic diversity is increasing in most advanced countries, driven mostly by sharp increases in immigration. In the long run immigration and diversity are likely to have important cultural, economic, fiscal, and developmental benefits. In the short run, however, immigration and ethnic diversity tend to reduce social solidarity and social capital. New evidence from the US suggests that in ethnically diverse neighbourhoods residents of all races tend to ‘hunker down’. Trust (even of one's own race) is lower, altruism and community cooperation rarer, friends fewer. In the long run, however, successful immigrant societies have overcome such fragmentation by creating new, cross-cutting forms of social solidarity and more encompassing identities. Illustrations of becoming comfortable with diversity are drawn from the US military, religious institutions, and earlier waves of American immigration.