This is a great approach, but I find myself not trusting Jellyfin's preauth security posture. I'm just too concerned about a remote unauthenticated exploit that 2fa does nothing to prevent.
As a result, I'm much happier having Jellyfin access gated behind tailscale or something similar, at which point brute force attacks against Jellyfin directly become impossible in normal operation and I don't sweat 2fa much anymore. This is also 100% client compatible as tailscale is transparent to the client, and also protects against brute force vs Jellyfin as direct network communication with Jellyfin isn't possible. And of course, Tailscale has a very tightly controlled preauth attack surface... essentially none of you use the free/commercial tailscale and even self-hosting headscale I'm much more inclined to trust their code as being security-concscious than Jellyfin's.