[ Read A.O. Scott’s spoiler-filled article about the ending of “Avengers: Infinity War.” ]

Those interesting, unusual specimens — what we used to think of, in simpler times, as “good movies” — aren’t exactly accidents. They are carefully planned exceptions that uphold a rule (meaning a regime as well as a norm) of passive acceptance disguised as enthusiasm. This universe is engineered for variety and inclusiveness, within certain strict parameters. Above all, the Disney-Marvel combination is a giant machine that manufactures maximum consent. The cosmos is theirs. The rest of us just live in it.

I’m not complaining, but rather pointing out how pointless, how silly it sounds when anyone bothers to venture a complaint. Who wants to be a hater? Still, it’s worth noting that the ascendance of Marvel (and of other, not quite as universal entities like it) has narrowed the parameters of criticism. I’m supposed to tell you, in this review, how much fun you’ll have at “Infinity War.” (Yes, you will have some. Will you have enough? Almost.) But I’ve probably already gone too far in trying to think about what it means. The Marvel movies and others of their kind often produce an illusion of profundity, a slick, murky overlay of allegorical suggestiveness. This provides grist for the kind of think pieces that spar with one another — “Infinity War” is liberal; no, it’s conservative; but don’t you see that it’s a protest against Trump; actually, it’s an attack on the tyranny of political correctness — until they catalyze the inevitable anti-intellectual backlash. It’s just a movie! Don’t spoil the fun!

And of course it is with respect to “spoilers” that the policing of discourse is most ruthlessly and effectively practiced. Reviewers who attend advance screenings take a vow of silence about plot details that will be widely known within a week and all but forgotten a week after that. Government secrets are guarded with less care, and requests from public officials to go off the record are addressed with more skepticism. But if I mention which superhero dies, or which one has an unexpected relationship with someone else — well, I wouldn’t dream of it. Not because I’m afraid of Disney executives. It’s the wrath of their obedient, weaponized minions I fear. In other words: you.

This is not a healthy situation. The reasonable concern that major plot elements not be divulged has spawned a phobic, hypersensitive taboo against public discussion of anything that happens onscreen. If, for example, I were to share that Thor (Chris Hemsworth) mistakes Rocket (Bradley Cooper), who is a raccoon, for a rabbit — whoops, you already hit “send,” didn’t you? The joke is repeated a half-dozen times, so it kind of ruins itself. And until the end, the whole thing is weirdly free of any but the most superficial, mechanical surprises.