I think that diversity in the workplace can only help a business. But it can also hinder it as well. If all those people were hired on a fair and even level, then it can only be beneficial to the work environment. But if those people were hired due to trying to create a diverse workplace, then it can cause problems.
Although businesses should not have diversity for diversity's sake, diversity does help a business. The more diverse a business is, the more unique viewpoints there are to provide interesting and new perspectives on issues and ideas. It also helps improve how well the people in the business get along with diverse individuals, such as customers from different areas.
When a diverse group of people surround each other, different perspectives are shared. This leads to fresh and new ideas in the work place. Also, it shows the company is socially responsible with the world's view of being acceptable of everyone. It promotes good customer relations my being diverse and accepting.
I'm going to assume that the creator of the poll is referring to diversity of race, ethnicity, culture, gender, etc. and not merely employees with a "diverse" set of skills or tools.
The problem with the contention that diversity is better for a business because you assumably have more diverse ideas is illogical because education creates a single culture. A "rainbow" team of accountants aren't somehow going to be more efficient or innovative than an all white team. Whether you are of Indian, African, Korean, Hispanic or what-have-you descent will not change the fact that you learned your skills, knowledge and education in a Western-centric system. Correct me if I'm wrong but I don't believe they have separate calculus curricula for women and men, do they? No they don't, so diversity is absolutely senseless in this sort of area. This goes for other lines of work too.
The only areas of business I can see diversity being somewhat of an asset would be possibly marketing and human resources, as well as some interpersonal service industries. However, even in those cases, it is A. Asinine to claim that someone who is white has no ability to understand a non-white culture and think like a non-white person and B. A burden for a business to force them to pick diversity over hard-working employees.
Diversity in the workplace hinders a business, because the person is not able to hire the people that they want to hire. Diversity is important because the person needs to be able to fit in at the work place, but at some point, the person also has to be qualified for the job.