I've seen a few people claim that the streak doesn't fit with a shot from the claimed location, because it's "horizontal".
Clearly it's not horizontal: it's angled down at the right. Eyeballing it does seem consistent with a rooftop shot from a low building some distance away: the angle from horizontal would not be that great. Presumably it would be possible to reconstruct the shot from the photographer's location (or at least angle, using the podium perspective, even if the distance wasn't known)?
Again this is hard to answer without knowing more about the rifle, specifically the settings on its sights.
As I'm sure you know as soon as a round leaves the muzzle it is subject to the effects of gravity. To compensate, the angle of the barrel (bore axis) will need to be raised slightly to launch the bullet at a slight angle as the range increases.
Just like throwing a ball. If you want it to travel farther you need to add an arc.
source = https://i0.wp.com/primaryandsecondary.com/wp-content/uploads/2017/06/FOTO_20170627_184920.jpg?ssl=1
Adjustable sights are graduated to help facilitate that. If you know your target is at 500m, you raise the sights to the corresponding setting.
This works fine in a target shooting setting but it's not practical in combat.
The compromise is to 'zero' the sights for a specific distance and leave them there. So at that distance, the rounds will impact where the sights are aimed.
Unfortunately, that means that at distances other than that for which the sights are zeroed, the round will impact higher or lower than the line of sight, but the variation is such that they will still land within a roughly man-sized area. So a case of 'good enough'.
The following image gives an example. Each target shows sights zeroed for a specific range (50, 100 & 300 yards). The red dots are for the point of aim. The black dots show where a bullet would land using the point of aim at the listed ranges.
So for example the far right target shows sights zeroed at 300 yards. The 300-yard dot is in the center of the red dot as expected. Look at the 100 & 200-yard dots. They are several inches higher than the point of aim.
source = https://www.thefirearmblog.com/blog/2016/07/14/awesome-free-targets-from-arma-dynamics/
The TLDR version is that the exact angle of trajectory of the round will depend upon how the rifle was zeroed.
Has anyone gotten a good estimate on the relative elevations of both the shooter & Mr Trump? That roof was not very high, and the former President was standing on an elevated stage.
----As an aside, USMC & Army SOP has been to zero rifles for 300 yards. That would allow any round fired from 0-300 yards to land within that vertical string on the target.
We know the rifle belonged to the shooter's father. We don't know who zeroed the rifle, what range it was zeroed for, or if it was zeroed at all. If the rifle was zeroed for 300 yards, it's possible the shooter was aiming center of mass and the rounds were higher than the point of aim because the shooter didn't understand how the weapon was setup.