Because there is actually something very interesting in Goodfellas, how the style of the film changes as time goes by and based on the mental state of the protagonist.
Quotes about goodfellas (3 Quotes)
But I never saw any review that actually analysed the shooting style of Goodfellas appropriately and they would just pick up on this one long take.
In Goodfellas they have this one scene where the camera goes down some steps and walks through a kitchen into a restaurant and the critics were all over this as evidence of the genius of Scorsese and Scorsese is a genius.