The problem is that the candidate doesn't know, its not even good proxy either way just like everything on the resume besides the list of companies the person worked on.

Most applicants have no idea about your internal HR procedures and what's the pipeline before the resume even gets from you so they might as well optimize for what generally seems the most "successful" approach. Maybe they actually think writing metrics and keywords is a good idea, maybe they think its stupid and resent it but can't get any interviews without it, its really impossible to tell without other variables..