Actually, CG doesn't enter into it. Godard made the statement several decades ago, long before CG - and when Godard did make a science fiction film, "Alphaville," it is notable in that it does not use any special effects. Godard, along with Truffaut, Rohmer, Chabrol and others were (mostly) only shooting existential parables in existing locations and available light. Therefore, the movement emphasized the 'naturalistic' elements of the medium, not the 'spectacle' aspects in the first place. I think that what Godard was most likely was expressing that film was a way of capturing a true moment...
...but I also think that he meant something a bit more by it. Cinema is, by nature, a construct. This is true whether it is a work of fiction or a documentary, whether it is abstract or naturalistic. Everything boils down to an inaccurate representation of an event as captured either by the chemical reaction of emulsion to exposure to light or by converting it into ones and zeros. It is also constructed through editing and, often enough, narrative. This is reflected in the mention of the standard 16, 35 and 70 millimeter* frame rate. This is not stretching; part of Godard's particular style included drawing attention to that very construction, usually through the use of very noticable editing (the opening sequence of Breathless is one of those that makes young people want to become filmmakers).
Furthermore, given the existential element of Godard's work, one must also acknowledge that his use of the word "truth," rather than something more concrete, like "reality," is significant. As remarked upon by a certain well-known (yet fictional) archaeology professor, "If it's truth you're looking for, Dr. Tyree's philosophy class is right down the hall." The word "truth" has a grander connotation to it, and I believe it refers to the momentary "truth" that is being created by the technological and artistic processes. The film becomes a truth unto itself.
I like how such a brisk statement can contain as much meaning as that.
* Todd AO and Omnivision both flirted briefly with 30 frames per second (Oklahoma! was one such production); Dynavision was another 65 millimeter format, but projected at 60 frames per second.