Later on, I realized I was watching and listening to just about everything via my computer or mp3 player so I began the process of ripping everything to my RAID (now just a standalone NAS).
Of course, I did sell those CDs and DVDs on craigslist afterward so that's just about as legally dubious as downloading unlicensed copies. I just figured I didn't need the stacks of plastic circles laying around anymore and could use the cash.
Either way, between rips and still occasionally buying mp3 albums on Amazon, I've got a load of digital media and Plex is an excellent way to stream it all to devices in my house. I use my phone or a laptop as the "remote" and the Plex server streams to my Chromecast, Xbox, or other computers from the NAS. It's a great setup. For people who want to use an Apple TV as their media extender, it looks like they have the option to use Plex as well.
Honestly this is a bit of a surprise since I thought Apple typically wanted to steer you toward iTunes for local media streaming but as someone who really doesn't like iTunes and generally avoids it whenever possible, Plex support makes Apple TV an actual option now.
Personally I just threw them away because I was fed up with them taking storage-space (which in my flat is limited).
This means I can't prove ownership, but at least I don't feel like I'm having some sort of moral dilemma around my digital collection.
It's also nice for us who have had a physical media collection (video & music) converted into a pure digital collection and want to be able easily to consume that anywhere, anywhere and on any device with zero friction.
Especially local media-sync is useful for long trans-atlantic flights and works much better (and space-efficiently) than just copying the full-fidelity files to the device, which in the end may not be capable of playing them properly at all.
Basically Plex is very good at completely eliminating issues regarding playback format and compatibility and ensures whatever is in your library always plays back correctly at whatever target-device you have.
I'm not going to deny that torrenters etc probably represent a big portion of the Plex user-base, but I'd like to remind people that actually owning your own media-collection is a still a thing, and I don't see any reason to make software managing such collections a suspicious category to be in.