Textures, audio, and 3D meshes and animations. TLOU is a very story-driven game in an open-world setting. Between the variety of environments, characters, and props, along with the sheer amount of dialogue needed to tell the story, the disc footprint can get huge quickly.
By comparison, Madden in particular doesn't really have much variety with respect to core gameplay content. Maybe 40 stadiums, little variety in player geometry, a few dozen sets of uniform textures (including rasters, normals, etc.), all the shared player audio, the entire bank of shared player animations, the QB-specific cadences, the commentary (all likely compressed to hell and back because it's just spoken word)... just not as much there to put on the disc.