This is basically because interviewers need to properly advertise the level of depth they want in a role. It's unfair to ask for each engineer to be in the top

This is basically because interviewers need to properly advertise the level of depth they want in a role. It's unfair to ask for each engineer to be in the top 5% of engineers everywhere -- not every engineer can be -- but there are roles that don't require such depth. But interviewing in general is tough (I'd go so far as to say it's a shitshow) and there's lies on both ends -- companies and managers and folks on the inside just want the best of the best -- and candidates just want a chance to get in the door -- the incentive to embellish is too high.