Yes and no. I do not think in that time frame that was being considered dictatorship. It was for the lack of legitimacy of Shah's case Mossadegh needed more power specially since parlemant was not that functional either.

You take Mossadegh's actions by the measures of the time. When I was reading about the history of the time, I fail to imagine what I could have done.

All in all, Iran's liberal movement by this coup might have been distroyed in a way it never did recover yet.