The fundamental philosophy at play here, I think - so far as there is one - is that government regulation cannot and should not be used to try and regulate away

The fundamental philosophy at play here, I think - so far as there is one - is that government regulation cannot and should not be used to try and regulate away the negative effects of lack of competition, that instead it should ensure that a competitive marketplace exists and let the market take care of it. If I recall correctly, there's an explanation of this position from Ajit Pai's FCC, which in particular references the NBC Universal-Comcast merger and explains why the FCC no longer wishes to allow such mergers.