Plex in particular is notoriously insecure. It should never be accessible to the open internet unless via a vpn like WireGuard. Just playing with fire otherwise.

Almost all selfhosted services are in that bucket now. Everything from Plex, Jellyfin, to nextcloud or gitea/forgejo. Few months ago I went through all my setup and moved everything to a vpn. The only service I kept public is a static directory served by nginx where I keep some html food recipes I shared with a friend before.

It's less convenient to use and pretty much impossible to share with others. I can figure out a VPN on all my devices for the most part (except for a Boox ereader). Trying to get "family and friends" to install and maintain a VPN on their devices to be able to access services I share with them is a pipe dream.

That may be true, but how do you grant non-technical family/friends access? They don't even understand what a VPN is, let alone how to toggle one on/off to access the Jellyfin instance.

Additionally, if they try to connect from an Android TV / Fire Stick, where you can't configure a VPN (and use their ISP's modem, so no wireguard client on the router to transparently route to the subnet), what are you supposed to do?

I feel it may be easier long-term to just contain the Jellyfin daemon to only r/o access to media, putting it behind a subdomain like jellyfin.example.com, and use the dns-01 challenge via LE to only provision a wildcard cert for the domain (IE *.example.com).

Then, have nginx listen on 80/443 with a default server directive that returns 444 for any requests not to the (correct) jellyfin hostname (due to bots hammering 80/443 across the internet on webserver's direct IPs).

Its the only solution I can think of to make it easy for nontechnical users (everything just described is completely invisible to a regular client) while reducing the attack surface area of the daemon.

FWIW, with the aforementioned setup, I got 0 unauthorized requests to my jellyfin server. Just a bunch of bots hammering my IP's 80/443 ports directly with exploits for old (usually wordpress) vulns, but they were all served 444 (IE an immediate TCP connection close without nginx even responding to the request).

Any citation for that or is that notoriety something that grew in your head?

Did you miss the point about working on random devices? That's the key to why I use Plex at all. If I have to install and set up a VPN client on it I'd just use Jellyfin because at that point I've limited myself to only my devices.

Also of course friends/family. The most technologically useless people I know can operate Plex and can access my collection with basically no support necessary.