There are two schools of thought in modern rap:
1.) People who hold up Tupac, Biggie, Wu-Tang as these infallible entities in rap of which all other rappers should be measured against and constantly compared to.
2.) People who understand rap, as a genre, is a living organism that is evolving as time goes on and celebrate deviations from the norm & innovations in the way bars are dropped, chosen lyrical themes, and production techniques.
The first school of thought is criminally flawed in its logic. Why would you even get into music if your pursuit was to worship dead people? This does not mean that people should put their copy of Ready To Die in the trash. The classics are the classics and that is eternal, but are they people that we can take cues on how to live from anymore? Jay Z is not a real person. He is married to Beyonce, owns multiple companies, and has an endless supply of money. The man doesn't even seem to have friends. He exists more as an abstraction in 2014. The same could be said for Outkast. The group's lyrics are quoted by Seth Rogen in his movies, Andre 3000 is a Hollywood actor, and the only gigs they seem to play anymore is on the White America festival circuit (Coachella, ACL, Bonaroo, Firefly, Governor's Ball). The point I'm making is that these rappers that people hold up as genre gods aren't people you can relate to anymore. When one of the biggest criteria for good rap is if its "real" (a term commonly used by the first school), shouldn't it say something about this school's taste that the rap they claim is real is being sung by unreal people? There's a famous adage about Bruce Springsteen and when his career started to go downhill. One day a fan said he didn't like Bruce anymore and a friend asked him why, the fan said "Bruce went from writing songs about people I know to writing songs about people I had only heard about."
The second school of thought is more ambitious in its scope and, while not perfect, is more innovative. One of the most admirable aspects about the rap genre is desire to build on the work of their predecessors as opposed to emulating them. Today's rapper goes into the studio asking himself, "how can I take what I like and bring it to the next level?" This is how we've seen the evolution of the modern rap game from the 80s / 90s NYC / LA scene to the 90s /00s Memphis scene to the 00s / 10s Atlanta scene to the 10s Chicago scene. It is an evolution. Rappers are conscious about their peers and their history and make music accordingly to it. It isn't like in guitar music when a band has a laser focus on a style / genre that they want to sound like and they work toward that end. An example of this in rap is Joey Bada$$, a New York rapper, who was a flavor of the week rapper that tried to bring it back to 1994 in his music. Joey is more the exception than the rule in rap. Other than that, the name of the game in rap is to outdo your peers and your heroes. If you're not trying to do something else, you shouldn't be doing it.
One of the hottest rap scenes ever (and I do mean ever, like it challenges 90s NYC for supremacy) is the current generation of Atlanta rappers. Led by Gucci Mane, the Chairman of 1017 Bricksquad, Atlanta has produced (in the last few years) Future, Young Dolph, Migos, Waka Flocka Flame, Young Scooter, Bloody Jay, Peewee Longway, Rich Homie Quan, and Young Thug. This doesn't even count the producers Atlanta has produced like Mike Will Made It, Zaytoven, and the 808 Mafia. Atlanta is a rap mecca.
22 year old Young Thug is a strange specimen. There's two viewpoints to Young Thug. The mainstream view & the initiated view. The mainstream view knows Thug primarily for his hit tracks "Stoner" & "Danny Glover" which don't really convey Thug's best essence anyway. They spend more time discussing Thug's use of autotune, his vocal delivery, and the "is he or isn't he gay cause it would be neat to have the first gay rapper come out" discussion (despite the fact everybody used their 'first gay rapper' ink for Frank Ocean only a few years ago). The initiated view of Thug paints a more interesting picture. The rapper's vocal style is erratic, it isn't composed and he sounds paranoid when he's rapping. On a lot of Thug's earlier works (the I Came From Nothing series), his themes are a lot more triumphant. He isn't a tortured soul living in this horrible world, as much as he's a guy who survived and life is great. Thug is more a celebration of survival than a eulogy for everything lost. His later works (the 1017 Thug series) bear some of the themes from ICFN but with some maturation to it.
Thug's vocal style is the way it is for one reason: he's a fighter and a survivor. Getting by in life isn't easy and not everyone sounds like Lincoln at Gettysburg when they talk about their struggles. The only thing harder than life itself is talking about it. When you listen to Thug and you hear the erratic / high pitched voice, it's real. What's behind it is real. It isn't a person who bought a compound in Paris to record their next single in seclusion. A lot of Thug's early stuff was recorded in a house in Atlanta with his friends around him. He'd hit a blunt, take a breath, and enter a makeshift recording booth that was probably a closet the producer converted. In a genre of music whose patrons hold realism as its highest virtue, there is no dishonesty greater than trying to deny Thug's authenticity.
Included are the I Came From Nothing & 1017 Thug trilogies as well as Thug's incredible collaboration tape with Gucci Mane, Young Thugga Mane La Flare.