most schools teach autodesk not blender. as a result there are alot more people that know auto desk, so there will be more people with talent that know autodesk than blender. if you are throwing around millions autodesk licensing will be a very minor part of the budget which makes sense to pay for with the larger talent pool. i don’t think you will every see a disney movie made with blender, and for fx pftracks, mocha etc seem to be much more in the major studios pipelines.
when you are talking about millions, thousands for a license is a non factor. if the people actually useing the license have learned autodesk in school trying to use blender to save money on licenses would probably cost far more in labor due to taking longer to work with unfamiliar software. the same would be true trying to force someone who knows blender to use autodesk. but there are probably 10 people that know autodesk for every person that knows blender, so the blender people are easier to replace.
i think blenders lack of documentation is why most schools dont teach it. if they would get good documentation more schools would teach it and eventually there would be as many skilled in blender as autodesk, then you would see major studios using it. but for now the talent pool is too small to take the risk when throwing around that kind of money. studios are businesses not charities. if they dont believe the have a good chance of making money off something they simply wont do it. for now autodesk is the safe route, just like making a sequal to last years block buster is the safer investment. art and innovation are fine concepts, but if they wont pay the bills you can’t make a living off it. people gotta eat, even artists.