Making games is way the fuck harder than making movies.
When you make a film, you can throw people at the problem. Adding more CGI people, gaffers, whatever to a late film makes it less late. Adding programmers to a late game makes it later.
Also, we've been making films for 100 years now. We've been making large-scale games for less than twenty.
We have a LOT to learn about scheduling game development, especially on projects that involve a lot of R&D like the leading-edge titles you mention.
Think you can do a better job? Head over to GamaSutra and start answering some of the help-wanted ads.