Just as with the recording industry, video technology based on digital processing rather than expensive magnetic tape and chemical film processing has changed the economics of production. The financial gatekeepers that guarded access to the major production facilities in Hollywood are dinosaurs of a bygone era.
What’s left is the expensive infrastructure of the craft unions, and of course, the star power of a small cohort of celebrities that still wield enough power to secure large chunks of the distribution profits for themselves. Netflix is the model for future distribution with simultaneous theatrical and streaming releases. The pressure on the existing system will eventually break the major film industry like it did the recording industry.
Even with digital technologies it takes money to make a decent theatrical film. Lots of money. People aren’t going to be making blockbuster hits out of their garage.