We'll have to see. China, Japan, Korea and India have world leading companies, world beating companies. They compare very well to more diverse countries like Mexico, Brazil, etc. [Japan and Korea are rather small compared to Brazil and Mexico]

This is separate from the question of providing fair and gainful employment for everyone --I think that's a goal as a society we should strive for _even if_ it puts us at a disadvantage. My question was more geared toward questioning the received wisdom.

One obvious advantage for companies operating in a homogenous society is they don't face the challenges in hiring a diverse workforce.