They way it works for me is, Hip-Hop is a very "out there" form of expression. When people get busy on the mic, being an authority figure plays a big part in it. For me, if I'm gonna take you seriously in the way you talk about yourself and other things in your raps, with authority, you gotta show me where that authority comes from. You can't be talking that talk to me and just be some random dude that has never been through anything. Hip-Hop is very braggadocious. So if you're gonna be talking like you're the man, being boastful about things, show me why.
Where did your authority come from all of a sudden then? Why are you acting hard?Do you have a reason to be acting like this?
Dudes that come from the bottom, from gangs, from poverty, other struggles, that shows me that you've been through stuff that can make you a "harder" person. You've been tested. You have a reason to talk with authority.
It's the fastest way to determine, with these "metrics".
Of course, this doesn't apply to all rappers/people, and this is not the "go to test" for that. There could very well be other reasons you become a "harder" person and that's fine. And you may not even be acting like the man in your raps, and that's fine as well.
Hip-Hop roots and foundation started in the projects, where being the man, the tough guy, has always been the thing. So it's no surprise it still plays a part of the genre today.