I could be completely wrong, but I think one of the first anomaly detection games was called “I’m on observation duty” which came out in 2018, but didn’t really get popular until late 2021 (when the fourth game in the series same out), about the same time “The exit 8” released funny enough.

That game is a little different where the player flips around security cameras and reports anomalies as they come up, but I think exit 8 was the first anomaly detection games that is “looping” and you have to decide whether to go forward or back depending on if there’s an anomaly