Don't depend on Dolphin videos to show you everything you are wanting to see shown to you.
They are TARGETED to isolate the illustrations to the specific topic of the video.
Here's a way to think about it:
The hard palate of the maxilla, otherwise know as the 'roof of your mouth' is also the 'floor' of the nose. Kind of like the ceiling in one's apartment is the floor of the person who lives above.
On a ceph diagram that marks out the points, this part of the maxilla is marked as ANS-PNS; anterior nasal spine to posteror nasal spine.
The ANS is the SUPPORT for the BASE of the nose.
A cut to displace this part of the maxilla cuts through (slightly above) the anterior nasal spine and takes the ANS for 'a ride' with it.
That 'ride' can be a number of displacements. The easiest one to start visualizing is 'linear advancement' meaning along the (same) 'line' or 'slope' ANS-PNS is oriented. In terms of an X, Y axis , diagonal lines either have a positive or negative slope.
The displacement of the ANS is what would be seen as a change to the base of the nose and sometimes right under the base of the nose at where the upper lip area (or labial ledge) is close to the base of the nose. So, when ANS-PNS is along a positive slope line, moving 'forward' with linear advancement will bring forward the base of the nose and the tip area is advanced and can rotate up slightly. For someone with a narrow nose base and a dorsal hump, it would improve the nose contour. But if they had a wide nose base and already upward tilted nose, it would just exaggerate that particular aesthetic problem.
If it's a sleep apnea case (with linear advancement) where they might have to advance out the ANS-PNS a LOT to accommodate a significant BSSO to open the airway, you want to look also at the CONTOUR of the ANS because the more the contour of it is pushed forward, the more CONVEX the labial ledge will become ('monkey lip). Here is a link where the doc seems to be doing linear advancement for sleep apnea cases.
https://www.sylvainchamberland.com/en/treated-cases/sleep-apnea_orthosurgery-treatment/ Here, you can see the positive ANS-PNS slopes in these cases and how a CONVEXITY to the nose/upper lip area can be kicked up when a LOT of advancement is needed for those extreme sleep apnea cases.
On the DOLPHIN video, well they did the illustration so that ANS-PNS was on a HORIZONT (not on a positive slope as in the real life extreme apnea cases above). Technically, moving the ANS forward in that illustration (IF they actually WANTED to show the lip changes to the labial ledge area between red border of upper lip and base of nose) would become less conCAVE as in a little straighter. But PRAGMATICALLY the lesson in illustration is to show airway and face balance changes in a cartoon of lucky person who is IDEAL candidate for maxing out aesthetics with linear advancement.
Combinations of rotations with impactions and advancements are more challenging to visualize and also to explain. Some people (eg. MIT types) can just to that in their heads (right side of brain) but hard (or just tedious) to verbalize it (left side of brain) or it just becomes a time intensive tutorial process to train someone elses brain to do that.
That said, my advice for 'brain training' to assist with understanding some of this stuff is to revisit Euclid as that type of rigorous observation training is needed as ground work so that a lot of these relationships (which relate to geometrical concepts) eventually become 'intuitive'.
By the way, the video does NOT show 'impaction'.