what would happen?

Stormtrooper misses, redshirt dies anyway.

Stormtrooper misses, hitting something else that falls on redshirt, easy.

Task failed successfully.
Plastic rocks. Plastic rocks fall on the redshirt
- the reason they have redshirts is to hide the color of blood.

I mean, the redshirt is there to show that the protagonists are in actual real danger. Just like the stormtroopers managed to hit every nameless rebel soldier on the Tantive IV they should be able to hit redshirts with incredible precision.

Yeah, they were intentionally missing Luke and friends so they could be tracked back to their base.
- That and a strong force affinity makes it harder (though not impossible) to get shot, kinda like a pathfinding "way of least bullets" direction.
Excluding clone-troopers and only in live acted Star Wars, Stormtroopers (sometime from off screen) have hit:
All kinds of rebels on various planets in "Andor"
A whole bunch of rebels in "rogue one"
A bunch of rebels on the Tantive IV
Leia (with a stunner) on the Tantive IV
All those poor Jaws, plus Luke's family.
The hull of the millennium falcon (to no effect)
A bunch of rebels on Hoth
C-3P0 in cloud city
Luke's lightsaber blade in cloud city
Leia on endor's forest moon
R2D2 on endor's forest moon
At least a few ewoks on endor's forest moon.
Din Djarin's beskar armor
A bunch of other mandaloroans and extras
Some of those turtle-riding aliens in a distant galaxy in "Asoka"
A bunch of innocent villagers on Jaku
Poe's parked X-wing (to great effect!)
Poe in the arm
Rei's lightsaber blade a bunch of times
The hull of the millennium falcon (again, to no effect)
I think stormtroopers are more effective than Klingons, federation red-shirts, or the borg.

Stormtrooper's only miss main karakters, the redshirt would be killed off to show how dangerous the empire was

Is the caption ragebait, invoking Cunningham's law? It's neither Schrödinger's nor a dilemma, it's a reverse irresistible force paradox.

Please don't mention that pedophile more than necessary, his cat's fame is more than enough.

The stormtrooper is female .... she fires, misses and nearly kills the redshirt ... reshirt recovers and the stormtrooper is so overwhelmed with grief that they become close friends ... after a six month relationship, they get married and a year later have a child ... the child turns out to be a half human half wookie ... the birth severely complicates their marriage

The half human-wook child grows up vengeful that their parents were both throwaways by their respective leadership. The child becomes the next emperor and destroys the Federation.
Have you considered a career as a writer? I would buy this book.

How is this a science meme?

Don't downplay the scientific importance of this question

Why is this AI? Surely these images are easily available

Changed it.
Old version:
- This changes the scenario significantly, though.
  Your original version had original series Stormtroopers, who are known to be crack shots and elites among the Empire's forces. There's a common misconception that they're bad aims, because in the first movie they were ordered to let Leia escape. They were showing tremendous marksmanship and discipline to miss all those shots while looking like they were trying to hit and allowing many of them to get killed in the process.
  Your new version has a First Order trooper. The First Order is some kind of weird fever dream that never really existed and whose capabilities varied wildly from movie to movie as the different writers and directors made up contradictory shit without any plan or consistency. So who knows.
  In both versions, the Starfleet security officer's famous flimsiness should be noted in the context we see it in - constantly encountering unique and/or wildly advanced threats. Little wonder so many of them died, they had no idea what they were up against.

https://youtu.be/Vh0l00Y1760

Shörider's dilemma