It doesn’t have to be porn for people to not want to know what they are watching to be shared.
I’m sure the RIAA is ecstatic that Plex knows what MP3s you have on your server, and when and where you listen to them. I’m sure they’re all 100% legally acquired, and you have the proper documents to back their up.
I’m sure your bible-thumping racist nan would love to know you watched Roots, or MSNBC, or anything LGBTQ. That’ll go over well. Especially if you’re in the closet.