I've been campaigning for kpop MVs to go 4k since before I got a 4k screen. Even for those still on 1080p there's many benefits, you can crop the MV, use screenshots of it and it still looks significantly better on YouTube in 4k on a 1080p screen. Of course, on a bigger 4k screen 1080p YouTube videos can be borderline unwatchable.
the MV goes for a bit of a retro style with sepia tones, narrow focus and contrast. I'm not too fond of this style, but it works. Here's what doesn't: there's film grain/noise. I can see why they did it, it makes a video much more "filmic" when it works. I'm not sure if they just turned of the noise reduction on cameras, or they added it in post. But neither really shouldn't be done when most people are going to be streaming the video on sites like YouTube. Videos on YouTube are rather starved for bandwidth but deals with this by using modern compression algorithms. The compression tries to group similar colors together as well as preserving things that didn't change between frames. Noise disrupts both of these. This leads to compression artifacts that both makes the noise pointless and lowers the quality of everything else.
On the left is Prisin Vs new MV, a static shot that has no business looking that bad. On the right is Laboums Hwi Hwi for comparison. Here's the full frame.
I admit, this isn't huge. But I noticed it within the first 30 seconds of the music video. It was probably just a newbie mistake, and I could have made it too. But still, some attention needs to be drawn to the issues or it's hard to improve.