Because not every movie and episode that I want to watch is already released. Radarr/sonarr lets me subscribe and downlod the correct movie/episode when available in the quality profile that I want.
Also automatically sorting everything in a useful structure when I share my plex libraries with friends and family.
You guys are not using radarr/sonarr?
Correct. But a VPN provider can also build a profile on that metadata, and transparency is often lacking in the VPN business. I live in a country with fairly good privacy laws for now and much prefer my ISP to have my metadata than someone else.
I trust my ISP more than a random VPN provider. I use HTTPS for everything anyways.
Different tools for different purposes