HELLDIVERS 2 Tech Blog #2 - Opt-in install size reduction beta (from 154Gb to 23Gb)
(store.steampowered.com)
Read the article before making assumptions. It's nothing to do with the artists.
They were deliberately duplicating all of their data to speed up load times for mechanical disks. Based on industry standard assumptions, they thought this was necessary. The article goes more into why it wasn't actually necessary after all. But it was nothing to do with the efficiency of their models and textures.