All videos have a massive constant "stutter" (feels like 3-5 frames per second). This occurs with streamed playback AND videos stored locally. The problem started after I updated the app (I hadn't updated it for many months, so I'm not sure what version I had).
I did basic troubleshooting like disconnecting all internet and playing a downloaded video, reset all settings, turned off any "experimental" settings on oculus, free'd up a ton of storage space etc. Nothing worked.
If you need confirmation that this is not an isolated problem, just check out the user reviews on oculus - there are many negative reviews describing this problem.
UPDATE: looks like all videos on all platforms are affected... going to try and rollback oculus updates