iOS Only - Using 2x storage for downloaded files

I can’t tell if this is a capacitor/Ionic/iOS thing?

When I download files to the DATA directory on my iOS device (but not on Android) using the @capacitor/file-system it uses 2x the storage space. The actual file is the correct size.

When I do this in a simulator and dig into the file system I find that there is a NetworkCache folder that is a duplicate size of the file I just downloaded?!

Who is creating this folder?
Is it iOS?
Is it going to get cleaned up at some point?

When my users download a 1GB file I don’t want it to use 2GB of their storage. But on iOS, that’s what it does and I don’t know how they can reclaim that short of deleting the app?!

What’s really bad is if I delete the file, that storage is reclaimed, but not what’s in NetworkCache folder?! So this completely useless data is un-reclaimable?!