Their first “stable” release was 6 months ago and they are currently working on the next major version #, so yeah, focus on recent posts only or the info will be out of date.

The reverse proxy is just to give it TLS with a let’s encrypt cert. If you are running an internet facing web application without TLS, Windows is the least of your concerns.

Put Jellyfin and a reverse proxy in an isolated vlan or DMZ, with no ability to reach into your lan at all and everyone connects in the same way. Its just movies, thats all you lose if it gets hacked. Set up some monitoring too in case it becomes a botnet node so you can destroy it and start over.