There are other mechanical components also that break or wear out. I recall a mention early on after the M-777 howitzers arrived that the US was surprised that they shot up a few months of ammo in one month.
The description of shooting special ammunition at too great a distance is a dumb statement. They are using standard types NATO munitions that the weapons are rated for.
One reason is they have been given too few tubes.
They need way more guns than they’ve got to shoot as much as they need to.