Too much compression, if nothing else. On a 4K monitor at full screen the jaggies and other issues reveal excessive compression that hamper it more than it should. The waxy facial detail also makes me think this is an upscale...
I then read previous responses and - yup, I was right. Upscaled. Not a shocker. That and this video had surely been posted before because I recall making the same patented whiny grumble about the ersatz 4K.

The shoulder pads on the uniforms should reveal a heck of a lot more detail, even in
that lighting and even considering it's a 1080P source. They're motionless for just long enough.
Still a lovely scene but no way does that pass, in full screen mode or otherwise, as anything approaching true 4K.
The overall scene with scenario and acting - still as magnificent as ever.