Buffering can help with performance for static HTML content. It has no benefit for Jellyfin and especially not for video content. It just uses more memory for no benefit.
Jellyfin 10.10.7 (Docker)
Ubuntu 24.04.2 LTS w/HWE
Intel i3 12100
Intel Arc A380
OS drive - SK Hynix P41 1TB
Storage
4x WD Red Pro 6TB CMR in RAIDZ1