If those linkages parts were missing, the loader would be pretty much unusable due to the shorter length of the cylinders. For a setup without the linkages, the cylinders have to be extended to get some decent curl and dump angles, so that definitely came from factory like that.
Whoever makes the loaders for the Branson 15 series also did this thing of removing that linkage and just increased the length of the cylinders and guess what, there are reports of bent cylinders almost every day.
I don't really think it's a quality issue, rather an engineering mess up. For a cylinder to hold those forces, regardless if it's the best cylinder in the world, it would need to stupidly oversized for the loader in hand.
That linkage makes an huge difference on applying the forces in the right directions for the cylinders, plus it reduces the overall length of the cylinders which will only make them stronger.
As if that wasn't enough, people see a loader and a backhoe on a tractor and expect them to work like a skidsteer and excavator. That just won't happen, specially with oversized implements.