Alan Mattli’s review published on Letterboxd:
Bad, but in a really perfidious way, where what's on screen could clearly be much worse, yet is so generic and slapdash that the lack of thought and effort that went into it becomes seriously grating after a while.
It's painfully obvious that a bunch of people with differring ideas and visions worked – partially separately – on this script, as it lacks even the most basic dramatic cohesion: there is no sense of set-up and pay-off, no foreshadowing or attempt at narrative ambiguity to speak of; every piece of information, both relevant and trivial, is stated outright, triply underscored on the dialogue level, and, at best, briefly revisited at a later point, without adding anything of note. Characters are introduced and dispatched without any dramatic urgency or reason: if you take the trouble to establish that Christos was a classmate of Adam's, why have him be nothing more than just another bland, functionally anonymous mini-boss (and another entry into the ignoble catalogue of villainous characters with facial scarring)? Why not give Zoe Saldaña a more fleshed-out introduction than casually dropping her in as a convenient deus ex machina?
Given the utter hollowness of the entire venture – including the maddeningly banal conspiracy plot – it's almost beside the point that the time-travel aspect is criminally malleable, so as to fit whatever derivative action beat or cheaply sentimental "character moment" (read: restatement of what has already been said multiple times, but this time, there is cloying music playing in the background) needs serving in the current scene.
The sad thing is that it's the movie itself that cheapens its own bids for emotionality: it's so beholden to its own pathological tongue-in-cheek quippiness that it barely ever manages to let a scene play out without someone undercutting its potential sincerity with a glib aside or self-aware reference. Once a movie has broken emotional tension using a fart joke, there is usually no way for it to still be credible as a heartfelt story about fatherhood and seizing the day.
Then again, even though Levy and his writers perfunctorily go through the motions of an earnest Spielbergian sci-fi coming-of-age tale, there is not much of an indication that they have any interest in their main characters as anything but conduits of plot: not only is earnestness continuously, and gleefully, shirked; there are also precious few moments where characters are made to confront their situation; and when they do, they just seem to repeat the same three boilerplate sentiments over and over again. It's nothing short of baffling to what degree this movie wastes Mark Ruffalo, both the actor and his character.
And of course, there is no visual flair to anything. There is some greenery to evoke E.T. (and to be bathed in some computer-generated evening light in the end), some concrete architecture to evoke late-stage Marvel, and interior shot upon interior shot that looks like Ryan Reynolds is about to break out into a sales pitch for locally sourced aspirin. I actually gasped in horror when they proudly revealed de-aged Catherine Keener.
On balance, I probably had a better time with this than Free Guy, likely because the latter delivered one of the most abysmal, most cynical climaxes in recent memory, whereas The Adam Project is content to just bask in its own unambitious mediocrity. But I think at this point, my tolerance for this kind of artistic laziness has run out.