Again as a relatively pure outsider, it is interesting to watch the internal competition between Disney Feature Animation's renderer [Hyperion] and Pixar's RenderMan, and similarly have been curious about how much of that externally visible open source standardizing work on at least the pipelines leading to the renderers contributes and/or constrains the friendly seeming internal rivalry. Similarly with Disney now owning ILM, if ILM has or has not been building on top of some of the same production pipeline standards...
Historically, a lot of the benefit to the Hollywood studio system was that a lot of the parts were standardized and interchangeable between studios. While a lot of studios did experiment with innovations in camera technology, very few studios had to reinvent the camera from scratch.
Given how many special effects houses work on a blockbuster level film these days, I would imagine that the efficiencies in shared asset pipelines between corporate boundaries would eventually win out. It seems silly (at least as an industry outsider) that every company working on, for one example, an Iron Man film would have a different set of models/textures/shaders for Iron Man. (I get that on the one hand it's a bit like stunt work in that you don't need your A-list actor in every stunt or B-roll shot, but on the other hand, digital "actors" don't get fatigued or injured and can be in multiple places at once, they don't need body doubles/stunt actors...)