I was really rather shocked to see this statement for it's such an inversion of the truth.
It is beyond question that every industry should be aiming for a workforce that is inclusive, non-discriminatory and accurately reflects the demographics of its market. As many companies are quick to acknowledge, this doesn't just make moral sense, it makes business sense.
It's an entire mockery of the most basic economic explanation of how wealth is created. Which is, as Our Adam pointed out, through the division and specialisation of labour and the trade in the resultant production. The implication of this is that far from our wanting the workforce of any particular industry to reflect the demographics of its market we want said workforce to be entirely different from the customers.
The point is most obvious at the extremes: we don't get babies to make nappies nor the crippled elderly install chairlifts. And it would be a very odd prostitute indeed who reflected the gender characteristics of her customer base (his, perhaps, her, no).
But when we abandon such extremes we're still in fact trying to do precisely the opposite of making the workforce the same as or reflect the characteristics of the customer base. Bakers employ people who both can and are willing to bake bread: bread is purchased from bakers by those who either cannot or do not wish to bake bread. And I'm certainly entirely happy that those who make airplanes are not as cackhanded as I am.
So it isn't just that we shouldn't worry about the demographics of the workforce, something that the impersonal activities of the market allow us to ignore. It's that the very functioning of the market, the very division and specialisation of labour that brings the market into existence as a means of distributing production, insists that far from wanting the workforce to be the same as the customers we're actually insisting that they must be different.
It's entirely true that certain forms of difference are not important: skin colour never, genitalia in only very specific circumstances and so on. But the idea that the workforce must reflect the customers is simply arrant, absolute, nonsense. For the entire point of the whole enterprise is that the skills, needs and desires of the two groups are different.