Anything that goes to production should have a 4-6+ eyes rule, at least one reviewer that can review the changes in isolation.

If tools or LLMs can help them with it then that's fine, but it should always be at least two humans involved, one making changes, one verifying, and if something like this happens, they're both culpable. Not that they should be blamed for it per se, but the process and their way of working should be reviewed.

Thu don’t check because the expectations are now to commit and merge often coming from higher ups.