>>5375529Well for one, many of their dinosaurs have pronated wrists and we know that those wouldn't work (same goes for us).
>>5375539Out of fleshy dinosaurs, I'd say revo t-rex. No elbow or wrist joints (as if it needs any) but perfectly fine in all other aspects. Other dinos fall short in ways like an inability to turn their head/neck or no tail. The WWD gorgosaurus (from the "ruined by talking" movie) is probably second place.
Skeleflex (pic related) are stylized skeleton dinosaurs and those are all ball joints. First waves are made of a more fragile plastic and prone to cracking.