When it comes to many (if not most) metrics, Tupac wasn't better than many of his peers. From a lyrical perspective he wasn't as complex as Nas, Big, or Hov. If you look at his albums it's hard to argue he has anything as good as Illmatic, OB4CL, The Infamous, and a host of other classic albums of that era. However Tupac's greatness can be traced to a few specific things.
1) Songwriting. Lyrical miracle rappers don't understand that being super lyrical and being a great songwriter are two different things. Tupac may not have been able to match Nas in terms of song concepts, but as a songwriter I think he was better than his peers. Bridges, hooks, and the simple yet poetic lyrics of many of his best songs.
2) Delivery. Not much I can add that Esch didn't. He's up there with Chuck D and Scarface in terms of having the best voices in rap, and his delivery of lyrics often made the lyrics work.
3) Image. The sex appeal part isn't the only factor. Tupac might be one of the most forceful, charismatic dudes to ever rap. He couldn't be fucked with in terms of standing up for what he believed in, and playing whatever role he was playing.
You can call him "fake" and laugh at his dance education all you want, but any black dude that shoots at police and beats the case isn't "fake" in my eyes. Anyone who refuses to get robbed and ultimately gets shot isn't faking. And lord knows anyone who outright
snitches on criminal kingpins and dares them to fuck with him again isn't faking. Rap is FULL of rappers pretending to be something they're not; shit is basically wrestling brehs, and just about everyone except the Wu Tang is lying about shit they allegedly did. But name me some rappers that didn't back down when tested outside of Pac. I'll wait.
