if you're using Hyper-V & WSL2 your distro state virtual disk image might be wasting 100GB+ of storage space. by default the VHDX grows dynamically but does not shrink if stuff is deleted.
to fix, launch powershell as admin, then:
wsl --shutdown
cd %LOCALAPPDATA%\Packages\CanonicalGroupLimited.UbuntuOnWindows_....\LocalState
optimize-vhd -Path .\ext4.vhdx -Mode full
afterward, you can also update wsl to the pre-release version and enable sparse disks:
