The tone is sort of half-campy – there are a couple of self-aware jabs, but for the most part, the conceit is played too straight to amuse with its silliness while also not providing hard-hitting thrills. In particular, the itch tag "Psychological Horror" feels completely irrelevant to the content of the VN. I guess it kind of feels like a case of "don't show the monster" taken too literally, since the game doesn't even have a proper action scene or tension sustained past a handful of text boxes; it's really just a vague horror thing happening in the background as the characters make a largely hurdleless escape. The final twist feels too abstract with how scarcely the mechanics and the feel of the thing are established, and the characterization doesn't have enough force behind it to make it land, either.
Also, while this is not my weightiest criticism, I think Mr. CinemaSins would have more than a couple of notes about the plot. A university research project inadvertently spreads some kind of spider zombie disease, a situation that takes place over several days, but literally nobody else seems to notice or care? Like, shouldn't the military be there shooting at stuff, or something? I'm not asking for a fully realistic treatise on how state authorities would respond to this kind of crisis, but the handwavy approach to worldbuilding makes the story come off as a loosely justified video game level.
As far as writing goes, the prose is pretty barebones, and having every sentence in its own text box makes the pacing feel really janky. But even being pretty short and hurried, Art Building is not the most economically written visual novel out there – the opening spends a lot of words on slife-of-life mundanity that does nothing to advance the story and little to characterize the main duo. It's kind of unfortunate that the arguably least important parts of the narrative get the most detailed and conscientious writing while the horror scenes rarely linger.
The sound design feels quite sparse in some parts – there is no alarm SFX despite it being prominently described in the narration – and the creature roar feels maybe too digital and distorted to really convey the impression of a monster chasing you. Meanwhile, the backgrounds are hurt by how empty some of the interiors are, with the titular art building consisting of a normal-looking office and a guitar in a vast collection of completely undecorated spaces. I think this contributes a lot to the video game-y feel of the piece. Not a strong package, all in all; I feel like it fails to stick to a tone and doesn't push the horror far enough.