Sure but that still doesn't address the actual problem and from a certain viewpoint two companies doing the same thing is less efficient than a large company doing it because of economies of scale. So which is it? Do we want efficiency or fairness?
Two companies doing the same thing brings the benefits of competition, which forces down prices, promotes innovation, and actually increases efficiency as they have to be better than their rival. In addition, no reason why both of them cannot be large enough to benefit from economies of scale (think Samsung vs Apple for smartphones).