I'm going to "third" this advice (though not the Plex part). Jellyfin is fantastic. Yes, you have to be careful which devices you use it on, because the client app isn't available for all smart TVs, but you can get around that by just buying a GoogleTV stick (like the $30 one from Onn) and plugging that into your TV; then you can install the JF app on it through the Play store (or even sideload it if you really want). I did this for my wife's parents, and it works great, and my own parents' Roku TV has the JF app in its store already.