I Always understood ''Fake Deep'' as mentioning issues but not going deep enough into to explore deeper issues with in that subject.
A Good Example of this is Logic. He speaks alot about race issues now don't get me wrong its great that he mentioned it but he never goes deep into
breaks stuff down, reference historic events the listeners may not have been privy too essentially teaching the listener something new.
I'm Not Saying a rapper has to teach you you can &
should teach yourself however if a rapper insists Swimming in the ocean he better learn to dive at some point
of course there is limit to how deep you can get on a 4min song because thats alot of info to be shoved in a song but a good example of this done right would be ''
Conflict diamonds'' By Lupe Fiasco
or this
or this even this
Of Course every song mentioning deep issues may not have been originally intended to be deep to begin with