I've used Plex for 10 years+ and Jellyfin for few months. Plex handles media recognition great and has an easy match function for the videos that aren't automatically recognized or need to be fixed. I have a few friends/family that I share my library with and it's easy for them to get connected remotely using their phones and roku/firestick without any issues using their plex accounts. I have the lifetime pass so my mobile devices connect for free but it there may be cost to install the mobile app.

Plex has expanded their free/ad-supported movies/tv shows but I have enough content I haven't explored it much. My server isn't very powerful so I can only have 2 streams going at once for my library which is mostly x265 content with a bunch of x264 content as well but that's enough for my needs.

I use a roku as my main client and besides some flakiness with the wifi from time to time it works fine, responsive and you can use the mobile app or http://remoku.tv/ as remote controls too in addition to the physical remote.

Plex is easy and works on everything I use it on. Easy enough that my old parents can use it. I know some people are bothered by their recent pivot to try to have some legitmacy but it's trivial to ignore their commercial-subsidized content

I hate Plex. It's gotten too bloated.

I run Emby primarily, but not externally accessible [vpn]. It works really well for me, haven't had any issues.

I use Jellyfin to put some stuff for the toddlers. It works on Amazon Fire Kids, while Emby doesn't. It works ok, but it's definitely less polished than Emby, and I feel like it's not as stable. Could just be me though.

Plex rocks, the lifetime subscription is worth it. If you want Roku Apps get a Roku and use the Roku to access Plex.

I would like to second the issues with Plex. I understand their desire to try and mainstream themselves and have a non-sketchy reason for people to still install them, but at some point it became too much of a mess and I went back to Kodi, which is great but not applicable for your use case

I've used all three and here is what I have most recently settled on: Jellyfin as a backend server with Infuse on the frontend. It has been rock solid for the last two years.

I've been running Plex for years (maybe a decade or more). Yes, there are a bunch of mainstream-ish features that I don't use. It's still simple for everyone in my family (including older parents) to navigate and use. I use it for movies, TV, and it runs a photo screen saver with family pics.