I think there are some weaknesses in D Breathnach’s piece.
For example, he makes a fair point about how revolutionaries who complain about how censorship lost them the revolution should pack it in. However, he later criticises the Provisional republican movement for not sufficiently challenging the revisionist hegemony during the conflict. Censorship did prevent this, at least in terms of the mainstream.
Where the Provisionals sought to challenge their detractors through self-published booklets – e.g. Freedom Struggle and Provos: Patriots or Terrorists? – their material was seized and people brought to court for possession of them.