I was aware of this director's style beforehand, as I had watched three of his films and heard about this particular one. I can't say that I spent the entire two hours in vain, because during the dull moments (about 65% of the total runtime), I was engrossed in my smartphone, and I won't criticize the film too harshly, even though it seemed rather empty to me.
I'll just mention the most obvious and, undoubtedly, over-discussed criticisms from the past half-century: watching a completely black screen for five minutes while suspenseful cacophony plays; watching rubber monkeys waving their arms wildly for 25 minutes; listening to the same repetitive classical music track for 40 minutes against the backdrop of a space station/space; enjoying psychedelic effects during an interstellar journey with distorted sound for 30 minutes – none of this is very interesting, and I don't think it was particularly engaging or profound even by the standards of its release year.
Everything else is quite watchable, despite its extreme slowness and superficiality. The film's underlying meaning, including the one and a half general themes it touches upon, as well as the plot itself, can be summarized in three sentences without much difficulty. Does stretching these ideas out over two and a half hours add artistic value? Sometimes, yes, but in this case, it seemed excessive to me. Are the one and a half general themes raised in this film deep and original? For its release year, perhaps, but does Kubrick's execution explore them in a way that they deserve? I'm not sure.
I'll also offer a commonplace compliment for the visuals – except for a few individual, somewhat comical details of the space-futuristic design, such as the corrugated limbs of the spacesuits, the gadgets, as well as the interior and exterior of the ships, look decent (five years later, "Moscow-Cassiopeia" was released, and today, it can only be viewed with a condescending, understanding smile from a post-Soviet person), and the color palette is quite pleasing to the eye.
In conclusion, I'll say: if you love space-themed films, don't watch this; you'll only see a general backdrop and a certain vibe in some parts of the runtime, but it won't satisfy your craving; if you enjoy serious plots or at least a subtle subtext to ponder, don't watch it; it won't live up to your expectations; if you have little time or are likely to regret spending it, or if you have a choice between vacuuming your apartment or watching this film, don't watch it; it won't be worth the effort; if you're an art-house enthusiast, are you sure this is the director you're interested in?; if you have a few free hours that you can spend without actively engaging, and you're not feeling particularly good, and you have a smartphone that you can dedicate at least an hour and a half to while watching the film, then you can probably watch it; it probably won't hurt. If you're a film school student, watch it; it's likely to be part of your curriculum.