Merry Christmas all I finally managed to get TSW 4 after my first attempt about a month ago failed for some reason. I looked at the Steam download time and had to double-look at 13 hours. I initially thought my internet was slow, but no. Since when did TSW become 139 GB?? From what I see on Steam, TSW 3 only requires 50GB of free storage, but TSW 4 requires almost 3 times that.
TSW is only 4GB of space. you may have disselected certain DLCs for TSW3 and/or gained new ones with your purchase of TSW4
My TSW4 install is 241 GB, and I don't have Vorarlberg or Maintalbahn or some of the other newer DLC. But the core install is only 4 GB or so.