[Samsung Galaxy Watch 4] adfree:
freshul:/ # mount -vo remount,rw /
try '/dev/block/dm-0' type 'ext4' on '/'
freshul:/ # cd /prism
freshul:/prism # ls -a1l
total 36
drwxr-xr-x 6 root root 4096 2008-12-31 15:00 .
drwxr-xr-x 27 root root 4096 2008-12-31 15:00 ..
drwxr-xr-x 3 root root 4096 2008-12-31 15:00 HWRDB
drwxr-xr-x 4 root root 4096 2008-12-31 15:00 etc
drwx------ 2 root root 16384 2008-12-31 15:00 lost+found
drwxr-xr-x 4 root root 4096 2008-12-31 15:00 sipdb
freshul:/prism # cd etc
freshul:/prism/etc # ls -a1l
total 36
drwxr-xr-x 4 root root 4096 2008-12-31 15:00 .
drwxr-xr-x 6 root root 4096 2008-12-31 15:00 ..
-rw-r--r-- 1 root root 14 2008-12-31 15:00 CSCVersion.txt
-rw-r--r-- 1 root root 932 2008-12-31 15:00 SW_Configuration.xml
drwxr-xr-x 13 root root 4096 2008-12-31 15:00 carriers
-rw-r--r-- 1 root root 4 2008-12-31 15:00 code
drwxr-xr-x 2 root root 4096 2008-12-31 15:00 init
-rw-r--r-- 1 root root 4 2008-12-31 15:00 sales_code.dat
-rw-r--r-- 1 root root 44 2008-12-31 15:00 sales_code_list.dat
freshul:/prism/etc # cd carriers
freshul:/prism/etc/carriers # ls -a1l
total 52
drwxr-xr-x 13 root root 4096 2008-12-31 15:00 .
drwxr-xr-x 4 root root 4096 2008-12-31 15:00 ..
drwxr-xr-x 2 root root 4096 2008-12-31 15:00 BRI
drwxr-xr-x 2 root root 4096 2008-12-31 15:00 KDI
drwxr-xr-x 2 root root 4096 2008-12-31 15:00 TGY
drwxr-xr-x 2 root root 4096 2008-12-31 15:00 THL
drwxr-xr-x 2 root root 4096 2008-12-31 15:00 XME
drwxr-xr-x 2 root root 4096 2008-12-31 15:00 XNZ
drwxr-xr-x 2 root root 4096 2008-12-31 15:00 XSA
drwxr-xr-x 2 root root 4096 2008-12-31 15:00 XSE
drwxr-xr-x 2 root root 4096 2008-12-31 15:00 XSP
drwxr-xr-x 2 root root 4096 2008-12-31 15:00 XTC
drwxr-xr-x 2 root root 4096 2008-12-31 15:00 XXV

Okidoki... reason for landing in XSA or depend on prism.img... is inside

/etc/sales_code.dat

I am on AUGF OLB on my SM-R875F...

Attempt 1.

freshul:/prism/etc/carriers # rm -r BRI
rm ro dir BRI (y/N):y
rm ro BRI/enforceskippingpackages.txt (y/N):y
rm: enforceskippingpackages.txt: Read-only file system
rm ro BRI/sales_code.dat (y/N):y
rm: sales_code.dat: Read-only file system
rm ro BRI/BRI_keystrings.dat (y/N):y
rm: BRI_keystrings.dat: Read-only file system
rm ro BRI/contents.db (y/N):y
rm: contents.db: Read-only file system
rm ro BRI/enforcedeletepackage.txt (y/N):y
rm: enforcedeletepackage.txt: Read-only file system
rm ro BRI/byoddeletepackagenames.txt (y/N):y
rm: byoddeletepackagenames.txt: Read-only file system

Ehm... need some time to think...

freshul:/prism/etc/carriers # mount -vo remount,rw /prism
try '/dev/block/platform/10500000.dwmmc0/by-name/prism' type 'ext4' on '/prism'

Edit 1.

Ah this work...

freshul:/prism/etc/carriers # rm -r BRI
freshul:/prism/etc/carriers # rm -r KDI
freshul:/prism/etc/carriers # rm -r THL
freshul:/prism/etc/carriers # rm -r XME
freshul:/prism/etc/carriers # rm -r XNZ
freshul:/prism/etc/carriers # rm -r XSA
freshul:/prism/etc/carriers # rm -r XSE
freshul:/prism/etc/carriers # rm -r XSP
freshul:/prism/etc/carriers # rm -r XTC
freshul:/prism/etc/carriers # rm -r XXV
freshul:/prism/etc/carriers # ls -a1l
total 12
drwxr-xr-x 3 root root 4096 2022-11-07 23:31 .
drwxr-xr-x 4 root root 4096 2008-12-31 15:00 ..
drwxr-xr-x 2 root root 4096 2008-12-31 15:00 TGY

Edit 2.

Reboot work so far but still XSA...

FAC Reset not tested... maybe better I edit salescode.dat to TGY before...

Now dumped...

freshul:/ # dd if=/dev/block/mmcblk0p31 of=/sdcard/dumpPRISM.bin
1228800+0 records in
1228800+0 records out
629145600 bytes (600 M) copied, 51.328983 s, 12 M/s

The hard part is IMHO valid for netOdin/Odin... also for my rooted device