"Modern scholars" do no such thing. You're talking about "modern" believers in the single-bullet theory (SBT), not "modern scholars" in general, because plenty of modern scholars view the SBT as a silly myth, and for good reason.

For one thing, in 2023, the most sophisticated, data-intensive SBT trajectory analysis ever done proved the SBT is impossible. It proved that JFK and Connally were never in a position to allow a trajectory back to the sixth-floor window. I refer, of course, to the 2023 SBT trajectory study done by the respected forensic engineering firm Knott Laboratory.

Knott Lab's experts conducted a high-definition laser scan of Dealey Plaza to generate a point cloud of up to 2 million points per second, to accurately measure point-to-point anywhere in the scene. Using a 3D laser scanner (Leica RTC360), Knott Lab's experts did 36 laser scans of Dealey Plaza, producing a digital reconstruction of the plaza that has 851 million data points. No other SBT trajectory analysis has included such a detailed digital model of the plaza and of JFK's and Connally's positions in the limousine.

FYI, Knott Lab's SBT trajectory analysis has been endorsed by the the Henry C. Lee Institute of Forensic Science and the journal Forensic. Indeed, Forensic did their own documentary on the JFK case using Knott Lab's SBT trajectory study.

Finally, it bears repeating that we now know that the back wound had no exit point, that there was no hole through JFK's tie, that there was no nick on either edge of the tie knot, and that numerous photos show that JFK's tie knot was neatly centered in the middle of the collar band during the Dallas motorcade.

JFK's Clothing Proves the Single-Bullet Theory Is Impossible
https://drive.google.com/file/d/1MAgWA0frOLVeWY6ok9nzdrgpRN4Wv1AL/view

The SBT was destroyed way back when we learned that there was no hole through the tie and no nick on the tie knot's left edge. Poof, there went the SBT up in smoke right then and there. But you SBT believers, acting curiously like Flat Earthers or 9/11 Truthers, simply refuse to process cold hard fact that abjectly refutes your theory.

It's called waving. After Z195 he stopped waving and began lowering his right arm, a movement he continued until Z226 when both arms suddenly raised dramatically. I don't see anything odd about it.

Andrew has painted himself in to a corner by fully committing to z312/313 as being the final shot of the three, clearly audible shots reported by over 160 witnesses.
JFK's reaction to being shot through the throat (and Brachial Plexus) is for his hands to fly upwards, towards his chin, at an incredible speed. It is clearly a neuromuscular/reflex reaction.
This indicates he was shot milliseconds before this movement.
The first reliable visible signs of this movement are seen in z225, so the shot passed through JFK only 2 or 3 Z-frames before this (z222/223).
The problem for Andrew is that there is a shade less than 5 seconds between z222/223 and z312/313.
He believes there was a significant gap between the first and second shots (and that the second and third shots were close together) - shot, pause, shot, shot.
This is impossible if you accept that the head shot was the last shot. There would be no time for a pause between the first two shots.

How does he overcome this problem?
By using the worst methodology possible.
He fixes the last shot at z312/313 then uses the time it takes to get off a shot with the MC (around 2.5 seconds ish) and calculates his way backwards from z312/313.
He then has his Z-frames (first shot z190, second shot z272, third shot z312/313)

After he has got his Z-frames he then, and only then, looks for evidence to support his calculations!!

He doesn't use the evidence to reach a conclusion.
He already has his conclusion and then cherry-picks evidence to support this conclusion.

It is a doomed method that led to a doomed theory.
However, this has not stopped him from constantly promoting this dead theory. It is his creation, after all.

Translation: "I still don't care, or at least I say don't care, because I have no idea how to explain the evidence that you're presenting.

And still nobody cares.