Call logs ('Recents') are lost when restoring an iTunes backup to iPhone

Restoring an iTunes backup doesn't restore the phone's call logs ('Recents'), so these are lost.

This is ridiculous. Why doesn't iTunes back these up properly? I can't find any mention from Apple that data will be lost when backing up and restoring.

I don't know if this is an iTunes defect (it hasn't had any updates for a while) or a new iOS 15 issue...there are so many other major iOS 15 bugs that I wouldn't be surprised. For example:

- Deleting voice memos, videos etc doesn't release or free up the memory storage space, even with settings set to 'Clear Deleted - Immediately'. The only way to make the space available is to completely delete the app itself, or update/restore the iPhone software via iTunes recovery mode.

- iPhone Storage reporting doesn't work properly. Sometimes it shows the space as occupied by the app data, sometimes as 'System Data' ('other' data). This seems random. Sometimes it shows an option to delete 'Recently deleted' files even when the 'Files' app shows 'Recently deleted' to already be empty.

- Outgoing calls are always fine, but incoming calls either cut out after ringing for a couple of seconds, or if they can be answered they are completely silent for both me and the caller. Sometimes the caller hears no ringing sound their end at all.

All this has caused me a lot of inconvenience. I'm unhappy that Apple has lost my data. I won't be buying any more Apple products...they're too flaky and unreliable.