So, I’ve got an old phone with 35GB of picture that I want to save. So far, I tried NextCloud sync, scp copy, GIO/NTP file. For all of those, it’s a 12h+ operation. And the real solution is to enable the developer mode on the phone and go straight to adb:
$ adb pull /sdcard/DCIM
/sdcard/DCIM/: 5825 files pulled. 31.9 MB/s (37517869453 bytes in 1122.166s)