I just don't know of any capitalist theorists who would present capitalism this way. I know of many who would argue that some degree of competition is good and necessary for capitalism, but is different from demanding every company have equal market share and equal revenue.

Peter Thiel in "Zero to One" makes an interesting case where he basically said he tried to avoid competition and instead just find a niche that no one else was doing. I think there's a genuine debate to be had over this topic even among capitalists.