On the 11 (R) to 12 (S) upgrade it probably would have been recommended to update the firmware by return to stock ROM. I did seem to find Stock ROM Android 12 (S) on this link (no idea how reliable) https://mirrors.lolinet.com/firmware/lenomola/nio/official/RETEU/. (But it worked ok for you.)
However the Android 13 (T) builds contain firmware parts which are expected to upgrade the firmware so “Return to stock ROM” + “Format data” are no longer a part of the process for Upgrade to T (from correctly installed S). Further it seems that Moto did not upgrade the device beyond Android 12 (S).
Format data may be significant if the data partition still contains “markers” for Android 11 (R) if it were the case that no Format data happened at the previous (11 → 12) upgrade.