Would it be theoretically possible to do a block-level backup of /dev/media without root? I have nothing against root except eFUSE. Whose ever idea eFUSE was . . .

As far as I understand: 
Because of amateur users and clueless minimalists who don't know how to utilise tools that are intended for power users, the development team of TWRP has controversially decided that their NANDROID backup does not include /data/media.

More information and sources in these comments:
  1. Best practice for backing up /data/media? 
  2. Best practice for backing up /data/media?

What I want is a block-level image backup of the entire phone, so that I can return to the exact spot later on.

I want that block-level backup to include the /data/media partition.

Now, I have found out it is possible via ADB, but that requires root. If there is really no other way, I would consider taking the risk of rooting the phone after doing any other possible backup method (adb app backup, file backup, etc.)

But my question is: 

Is it technically possible to do a block-level (dd) backup of the /data/media partition without root?

Had the developement team of TWRP decided to include /data/media, pleasing power users and maximalists instead of minimalists and amateur users, would it actually have been possible without root?
Is it technically possible to do a block-level (dd) backup of a file? - Yes
Is it technically possible to do a block-level (dd) backup of a folder? - No