So we just fire all the employees and hire better ones only because someone did not pay attention to the comment.
Of course it is an exaggeration - but also in the same line people who think "others are failing at their jobs" - should pick up and do all the work there is to be done and see how long they go until they miss something or make a mistake.
Solution should be systematic to prevent people from failing and not expecting "someone doing their job properly".
Not having comments as something that needs a review reduces workload on everyone involved.
Besides, interfaces for PRs they clearly mark what changed - they don't point what hasn't been changed. So naturally people review what has changed. You still get the context of course and can see couple lines above and below... But still I blame the tool not people.
It sounds like people are failing at their jobs.