Helldivers 2 developers recently discontinued support for the old "fat" client on PC. Now all players are using a lighter version.
Instead of 140-150 GB, Helldivers 2 takes up just over 20 GB on the drive — previously, the large size was explained by HDD support. The data was duplicated to speed up loading on such drives.
However, Arrowhead Game Studios conducted tests and were able to find a solution to optimize the file size of Helldivers 2. HDD owners can still play, but the game now takes up much less space.