Comment by kccqzy

In practice the difference is whether the code that does this reclaiming is actually working. I’ve never gotten my Mac into a low disk space situation (other than maybe in Leopard days) but on iOS, it is quite frequent for me to trigger a situation where the free space including purgeable space is many gigabytes but actual free space is nil. Trying to commit a transaction in a SQLite database in an app? Sorry you can’t, there’s no space left on device. Now go to settings and observe that you have 15 GB left (which includes purgeable space). Even SpringBoard has trouble showing icons. I do not trust Apple’s OS level disk space purging at all. I trust the filesystem and the storage medium more.