I'm relatively new to VR gaming, but I belive whats happening is that your VR headset doesn't receive the next frame to render, and it injects whats called a synthesized frame that ultimately doesnt help at all, as the mainthread is almost completely locked during loading and it makes the image jump around like that. During gameplay it will happen if you have framedrops.
Personally on my rig, with a now 'older' 7700k I cant really use oculus link as the video encoder sucks up too much cpu time (quest 2 isnt a native pc vr headset so it encodes the display as a video), but Virtual Desktop works fine for me as it presumably uses a less intensive encoder.
Regardless this really isnt a bug on DCS side, although one can wish it didnt completely stall the render during loading