It might be unfair to call Def Jam: Fight for NY the greatest hip-hop game of all time, as the number of entries in that specific subgenre is minimal. There are innumerable games that borrow the hip hop aesthetic and even more games that feature real-life rappers, but very few are about hip-hop. That's definitely strange considering how commercial rap has become in the last twenty years. One would imagine that we would've had at least one Lil Wayne or Kanye West game by now, but, alas, reality is often disappointing.
Def Jam: Fight for NY doesn't just earn the title of greatest hip hop game by default, though. Anyone who's ever played the game knows that it's easily the highest quality rap video game around. Despite how fantastically bonkers 50 Cent's game is, Def Jam: Fight for NY somehow eclipses it in scale and style. Hip Hop Madness's YouTube channel explains what made Def Jam: Fight for NY so legendary in the video linked above.