Correct. Only reason to tether the Oculus Quest 2 is due to a game's high end GPU needs. Games like Alyx or No Man's Sky require tether, games like Vader Immortal ( insanely fun - although short ) do not. Any 360 video, image viewing can be done without tether.This is a pretty good point, and I'm assuming the Oculus Quest 2 can view such content without tethering to a PC?
For full understanding: you may tether to copy across movie files from PC to Oculus.