I can see how that would be true for some types of development, but there are also many type for which I don't see offhand how it would matter.
For instance, if I were doing web design for my employer's shopping cart site I could see how having a diverse team could greatly help because the team would have people on it that are part of or identify with more of our customer demographics.
I as a white male mid-50s atheist tall fat guy could easily inadvertently come up with a design that might turn off non-whites, females, young people or elderly people, religious people, short people, or skinny people. Even if I don't end up doing something to offend people, I could simply miss opportunities that people of other backgrounds might see.
In fact, I've seen that kind of thing. I saw a company that was making CD-ROM caching software in the '90s find a nice cluster of sales when an employee who was also a Mormon pointed out that this software worked extremely well with the CD-ROM genealogy databases that were becoming quite popular among Mormons. Without that Mormon employee, they would have probably never noticed that Mormons could be a distinct market segment for this product that was worth specifically targeting.
What I actually work on, though, is backend stuff like processing orders and subscription billing, interfacing to payment processors, reporting sales tax in the US and VAT in Europe, analyzing A/B tests, and so on. Would having a diverse team working on this actually produce any different results?
It's partly up to us to make diversity happen. We can prioritize offers that have diverse teams, and when we get a chance to hire to value diversity of experience.
[0] http://carlos.bueno.org/2014/06/mirrortocracy.html