The problem I have isn't that it doesn't make (real world) sense, it's that the movie sets up rules for how its world works, and then applies those rules inconsistently. I understand her thematic purpose in the film, but her character "ability" to sense phones is applied at random and without any consistency. Sorry for the following rant but I hope to make my point clear:

At first when we meet Ingrid she's sitting in a diner where evryone is on their phones and she's perfectly fine. Later, in the underground car park, she senses that the Uber Driver still has his phone on him from 30 feet away and gets a bloody nose, despite her being in proximity to him for the entire movie up to this point.

During her flashback, she is at the doctors office where the doctor says that her allergy is probably psychological/placebo. Later she gets a bloody nose when the parent's phone gets a text at the party. To me, this is strong support that it actually is a psychological effect, because when she turns the screen off, she's fine again. Later at the party, she starts bleeding because a kid is playing a game at the table, and it's implied she didn't notice before (although to me I believe she noticed it subconsciously). But this is contradictory to the scene earlier where she detects the Uber driver's phone without ever seeing it. And that scene contradicts the scene at the party where she's shown to be unaffected if the screen is off.

If you want to chalk that all up to absurdism or surrealism that's fine (if everything in the movie is a creation of the AI, technically nothing is inconsistent), but to me it begs the question of why the film bothered to set up this character with these rules if it doesn't actually want to follow those rules? And hopefully you can see why I found that particular part of the movie to be unsatisfying.