http://valinet6l6tq6d5yohaa6gdsf2ho4qcqcxyj2nahp5kd4z7nsa6ycdqd.onion/2021/01/20/Automatically-backup-the-iPhone-to-the-Raspberry-Pi.html
When I was using Android, I did not have such a problem, as I manually copied the photos to the PC once in a while or automatically to Google Photos before Google borked the service , while the phone synced its settings with the Google account and WhatsApp was syncing up with a much beefier 20GB Google Drive account. It pretty much worked out. Since switching to an iPhone, backing up WhatsApp became a problem.