@Wireath
Yeah,
@Robbini is right here.
They
could have done it, but with little manpower, an arrow barrage would not have done a whole lot.
In reality, arrow barrages weren't really all that dangerous(compared to everything else at least)
But were still important because it prevented footsoldiers from advancing on the archer's positions easily without taking casualties.
Medieval warfare was more focused on cavalry then archers and footsoldiers anyway.
Not to mention that even without magic arrow barrages has abysmal accuracy and is fairly easy to defend against by anyone who has a large enough shield.
With that said, even a shield wall isn't perfect and the odd solider still died here and there.
But it wasn't a resource-effective way to kill people and with limited manpower and the availability of better options,
like a freaking flame thrower.
it's better to save the arrows for normal straight shooting to save ammunition.