All of them are hired by the production company. They don't get any share of the copyright. As long as the film is made with decent budget, they'll get hired whether or not copyright exists.
Those words "made with a decent budget" are where I have trouble with this argument. Of course the supporting staff are paid out of an overall project budget, but if anyone is free to copy and redistribute a work as soon as it's available, do you really think it's going to be worth investing the same scale of money in making it? I just don't think that is a credible position to take.
Works like feature films could still make some money, of course, for example via cinematic release where your customers are paying for the experience and never have direct control of the material. But things like DVD/Blu-Ray and on-line distribution are dead, and those increasingly represent the bulk of the profits in the movie industry.
Do you realize that the existence of current copyright-backed content industry leaves very little space for evolution of any alternative economic model?
Nonsense. There is absolutely nothing about today's copyright landscape stopping someone from funding a new work via pre-copyright mechanisms like patronage. With the ability to crowdsource on the Internet, there are potentially interesting new options as well. And yet so far, the biggest successes from the likes of Kickstarter are still orders of magnitude smaller than Hollywood blockbusters or AAA games, and the closest example we have to major patronage is probably big commercial contributors to Open Source in the software world, which usually have self-interest as a significant motivation and then share the results because they have no reason not to.
One of the most promising alternative models today is that a single creator or small group who know what they're doing can now viably go it alone and make real money by marketing and selling on-line. Old middleman services like book publishers and music studios are under a real threat of being out-competed by (or turning themselves into) service providers that work for the creative people, not the other way around. This is great news for returning the power and lost of the rewards to the people actually doing the creative work, and bad news for anyone who's been comfortably brokering deals but adding little real value for years. But this approach doesn't scale to large team, high production value, mass market products as it stands.
Any open-source software that's widely used in business environment reaches commercial quality pretty quickly.
For geek tools -- servers, software development, networking tools, that kind of thing -- sure.
For mainstream business use, I contend that no Open Source software exists today that is widely used in business environments, and that the Open Source software that is used in small parts of the business world outside of geekdom is rarely of the same quality as traditional commercial alternatives and is chosen for other reasons. I hate coughing up for Office and Creative Suite as much as the next business owner, and I have a pretty low opinion of both Microsoft's and Adobe's recent offerings compared to what they've made in the past. Even so, the idea that LibreOffice and the GIMP are credible replacements for general business use is still as absurd today as it always has been.
But software world will be taken over by open-source software anyway because current proprietary software giants don't have the same power over the entire software market as Hollywood does over culture.
The proprietary software giants don't need the same kind of power. They make better products, and will continue to do so for a long time. Most of the people who would chose the OSS alternative were never going to pay the proprietary/commercial vendors for their product anyway, because piracy.
This might change in the long term, but I'm not convinced it will happen even then. At the moment, it appears that even relatively popular OSS products, where it's possible to attract a large enough volunteer team to build large-scale applications, still can't keep up with the proprietary/commercial competition. Once again, the exception is areas attractive to geeks, and the best examples are things like LibreOffice and the GIMP.