So this part? Profile Information. You may provide us with profile information such as your e-mail address, username, a profile image, and password when you create an account, or when you edit your account information. You may also provide us with your payment information when you sign-up for a paid service.
OMG, they're...storing the login info you gave them
Literally the whole thing, other than the bullshit at the beginning about how deeply they care about your privacy, is about information they collect about you. That's what a privacy policy is.
The only plus I can see is a focus on DLNA might make DLNA not _strictly_ garbage. In reality if you don't want to use Plex and don't need to rely on DLNA, there's other options out there like Jellyfin or Emby.
Jellyfin is great... client apps for roku & ios plus a web interface cover all my devices. Minimal setup, just run it from a docker container. Has been super stable for me for a few years now.
https://jellyfin.org/
Jellyfin has had “coming soon” next to Samsung and LG tvs for over 2-3 years. Not much use without native apps considering how awful the built in browsers are.
I found it awful, on a Raspberry pi 4. Scanning through 2TB of movies on a NAS (gbit nic) took days. No visible indication of progress or where it's stuck. When it's done and there's a load of stuff missing, there's no clear way to find out what it ignored and why, so all you can do it manually go through every movie that it didn't find (easier said than done). I fought with it for 2 weeks and dumped it for Kodi and a direct attached 4tb hdd. Kodi finished the scan super quick and just works.
I used to use this to make media available to a PlayStation 3. It can do on-the-fly conversion for codecs that aren't supported by the client, though I think Plex can do that kind of thing too.
Nowadays, I use TinyMediaManager to tag all my film and series and make them available to a Raspberry Pi running Kodi/Libreelec. I also tried using JellyFin as there's a good Kodi plugin for that, but prefer giving the Kodi box direct access to the files - seems to work better for keeping its library up to date.