A lot of people were super annoyed coming from WinAmp. They organized their library by filename and the metadata was often a mess. They also wanted to treat iPods as USB drive and drop files on there.
Plex is even different in that it only looks at the filename and pulls metadata from the Internet.
Nope. Had no idea. And no idea why I should, since iTunes has no problem with it. I'm not going to spend six hours sorting 4GB of files because Plex can't read metadata that iTunes can.
We're running the Plex app on an AppleTV (4th gen, not 4K), and it all works really well. The only issue is that it loses connection to the server maybe once every month or two, but I think that's related to my really crappy modem.
edit: Plex server is running on the 2012 Mac mini "Server" edition. Quad-core, baby!
For some reason Plex wouldn't see half of my video library. I eventually tracked it down to Plex not liking the filenames of certain TV shows.
My TV shows are named Show Name - Episode Name.
Plex wanted them to be ShowName.s0x.e0x.
I'm not going to go through and rename all of my files. Plex should just work from the metadata like iTunes does. That's what metadata is for.