No idea I’d thats a common thing in AI video

As far as I’m aware, it’s not. Most AI video is consistently clear, or at most just low resolution. (i.e. it tends to maintain a consistent visual style for each clip, without much changing to composition, lighting, style, depth of field, etc)

I was originally inclined to think that the blurring was added in post, to cover up moments where the AI generated footage did something that made it obvious it was AI, but even regardless of that the faces, positioning, and lighting in the background remained pretty consistent across the length of the video, which AI tends to not be very good with. (i.e. in a crowd of people faces will randomly appear, disappear, move, change height, etc in a way that’s unnatural)