@Animosity022
MacOS
I believe some of the smaller chunks are MacOS attempting generate thumbnails after the volume is mounted... But other than that I'm still at a loss.
I increased VLC's buffer to 1.5 seconds and that smoothed things out a bit. However QuickTime Player doesn't have a way to adjust the buffer, so it still does not seek properly.
In fact, trying to play a 1080p video in QuickTime Player will, I kid you not, take down the entire system.
First it pinwheels, the only option is to force quit QT Player. The pinwheel remains. Killing rclone mount does nothing. Attempting to eject the drive in Finder does nothing. Force-relaunching the Finder causes Finder to exit but not reload. The system is then unusable until reboot.
Literally the only non-privileged app/non-kext I've ever seen able render MacOS unusable.