Transfer progress bar finishes too fast

### What Happened?

Even if I copy a relatively large file to a relatively slow (usb stick) destination, the progress bar appears to finish unrealistically quickly.

The actual transfer is still in progress (kernel cache?) and if I (a average Joe user) unplug the usb it might result in data loss? Certainly if I (a little more savvy average Joe) click the unmount button it just spins for a long while until the transfer completes during which time I might wonder whether something has hung.

### Steps to Reproduce

See:

https://github.com/user-attachments/assets/1c264998-69c7-4bba-993a-635e35de5d36

### Expected Behavior

Progress bar should be realistic.

### OS Version

Early Access

### OS Architecture

amd64 (on most hardwares)

### Session Type

Secure Session (Wayland, This is the default)

### Software Version

Latest release (I have run all updates)

### Log Output

```shell

```

### Hardware Info

_No response_