With EXT4 it would just use standard linux permissions on the directories in it. What intael post is describing is for NTFS and would not apply to EXT4.
Jellyfin 10.10.6 (Docker)
Ubuntu 24.04 LTS
Intel i3 12100
Intel Arc A380
OS drive - SK Hynix P41 1TB
Storage
3x WD Red Pro 6TB CMR in RAIDZ1 (JF Library)