Neil Alcock’s review published on Letterboxd :
Fusing the spirit of the TV series with a faux-2001: A Space Odyssey ponderousness, Star Trek: The Motion(less) Picture sees Kirk and co accompanied by two personality-free carbon units and dressed in a series of increasingly unflattering costumes as they attempt to stop a big space thing from doing a bad thing to other things. They achieve this by spending almost the entire film on one small set while VFX technicians run a test reel of all the whizzy things they've made on a big screen in front of them.
It's not without its charm, and the scene in which the Enterprise loiters outside a giant alien sphincter like some intergalactic haemorrhoid is, at least, unintentionally chucklesome. Unfortunately the film's energy is crippled by its catatonic pace, and the central concept - both Spock and the alien force seek more than pure logic in order to truly live - is buried beneath turgid scenes of people literally staring into space and Jerry Goldsmith's deafening TWAAAANNNNNGs (which predate the Zimmer BRRAAAAHHMMMM by three decades).
That said, when the ending features a crew member shagging a 300-year-old satellite in order to save the human race, it can't all be bad.