This is the core of the "gta 5 60gb" debate. Gamers with 256GB or 512GB SSDs are desperate to shave off those extra 40GB. However, reducing the game to exactly 60GB comes with caveats.
Are you running into an or a low storage warning ?
Expect the game to occupy between 110GB and 120GB of space on your storage drive today. GTA 5 System Requirements
The map is incredibly detailed. Every building, streetlamp, vehicle, and pedestrian model requires storage space.