Diversity of what? People vary tremendously. Some are detail-oriented, some see the big picture. Some work well in teams, others work best independently. Some bring a intuitive sensibility, others are meticulous. These are ways in which teams benefit from diversity.

For teams to benefited from racial diversity, race would need to correlate strongly to some kind of psychological profile. Something that's meaningful in the workplace. Is that really what you're saying? "Asian people are [psychological trail], whites are [different psychological trait], indigenous Canadians are [another trait]? 

Canada has made tremendous progress on social issues by moving away from that identarian thinking? It's appalling that so many want to throw away that liberal progress by returning to a world where the most important thing about someone is their race, gender, or religion. It's reckless folly.