Yes, ensuring the market is contestable stimulates production. No one wastes time producing products for a market they cannot enter. But this does not guarantee the survival of the new products -- or of the existing cartel-supplied products. The whole point about making the $#@! market contestable is to produce the purported benefit of competition by allowing consumers to chose the superior good. This may, in fact, lead to a net decrease in the variety of goods if the new entrant is sufficiently superior. The central question is not therefore whether we have "enough" competition but whether competition is actually possible.
Accordingly, the FCC's calculation on what it takes for a cable channel to achieve viability is not about "adding channels." It is about enhancing competition between channels, as specifically mandated by Section 613(f).
Ignorance is excusable. Dismissing critical economic distinctions as "rhetoric" is not.