Yes, but that's technically still 4 new ships at the time.ANH had only X-wings, Y-wings Tie Fighters and Vader's Advanced if I recall correctly (as far as fighters go at least).
ESB added the TIE Bomber, and RotJ added A-Wings, B-Wings and Interceptors.
TFA added zero new ships. Just new models of old ships.
Don't forget the Firespray in ESB. And they had several ground/air vehicles (which are obviously not relevant for X-Wing).