For anyone who’s still experiencing the System Data storage bug - I found a solution you should try.
My System Data was at about 19GB, completely filling the free storage of my 64GB iPhone. I tried backing my phone up to my Mac, as some people have had success with that, but it didn’t help.
Today, I went to submit a bug report via the Feedback App. I started collecting the storage logs and then left it going to go take a screenshot of the storage to attach to the report. To my amazement, it had dropped down to a much more respectable 9GB!!! Collecting the storage logs significantly reduced the System Data storage, without even needing to send it! (I did send the report afterwards with a note explaining what had happened, though.)
If anyone is shuffling to fix the System Data issue, I encourage you to do what I did.
- Open Feedback (applefeedback:// in Safari)
- Create a new report
- Area of Issue: Settings
- Part of Settings: iPad/iPhone Storage
- Scroll down and hit “Gather iOS Storage Logs”
- Profit!