Mr. DuLac’s review published on Letterboxd :
It's life, Captain, but not life as we know it.
That quote could be changed to "It's Star Trek, Captain, but not Star Trek as we know it." This bloated mess of a film seems to take it's visual queues from films like 2001: A Space Odyssey instead of the television series it's based on. As a result the 90 minute story is ballooned to a 132 minute running time with most of the filler being that of a film that seems to be in awe of it's own visual effects.
The visuals are impressive however, but scenes like the introduction of the new Enterprise and later on it's passage within the space cloud are both pacing nightmares. While it can be argued that a film like 2001 implored the same techniques, the difference here is that these scenes have nothing emotional or important to dwell on. Underneath all that filler does lie a damn good science fiction story however. It should be noted though that the film feels like an overblown Star Trek episode because it actually is one.
Paramount Pictures had originally shelved the idea of a Star Trek film and had green lighted a followup television series, Star Trek: Phase II, to start airing in 1978. Sets were built, costumes were designed, new characters were cast and test footage was shot when Paramount abandoned the series at the 11th hour in favor of a motion picture. Scrambling for a script they adapted what was going to be the premiere episode of the new series, "In Thy Image", into what is now known as Star Trek: The Motion Picture. The characters of Decker and Ilia were actually going to be regular characters on the show but made it to the film mostly intact.
While the filler and pacing are the film's biggest problems, it also suffers from not having the camaraderie and fun tone from the original series. Shatner, Nimoy and Kelley were the heart and soul of the original series and here they are mostly overly serious and grim throughout the film. Director Robert Wise takes a lot of flak for this film, but taking into consideration the extremely rushed production and crippled script he had to work with, I think he managed to churn out a visually stunning flawed film that has a great little sci-fi story hidden underneath.