That’s so weird. I’ve been using Plex for years and had never heard of “Passout Protection” until looking it up just now, nor does it ever stop playback on its own for me unless it reaches the end of the queue. I’m using the free version via web browser on my computer. Maybe it’s a setting that only affects apps? Continuous playback on Plex is one of the reasons why I’ve always preferred it over Netflix, etc.