The major annoyance with that is that you have to explain to your parents/friends how to do that when you give them access otherwise they won’t find your stuff in the ocean of media plex is trying to push at them.
You also have to now trust that they have a secure password and don’t share/get them compromised.
I picked Emby for many reasons and one being local accounts I control. Plex pushing you to use their accounts (and then pushing streaming content like this) just wasn’t an option.
I built a thing that integrates with my ISP's TV API and makes it look to Plex like an HDHomeRun tuner. It also generates XMLTV EPG (again, based on my ISP's data) so that I don't have to faff around with third-party EPG providers and with channel matching.
So as far as Plex is concerned, this is an HDHomeRun tuner + XMLTV EPG.
I can also tune directly into any of the TV streams using VLC, in one of three ways:
1. raw MPEG transport stream over UDP multicast
2. same stream over HTTP (via udpxy)
3. my ISP's transcoded HLS stream (lagging by a few seconds and missing certain features)
I've done this and the only things that I see in my Plex app are locally-stored contents and my TV channels (delivered over IP by my ISP).