Some work just requires longer hours. I've worked on a couple of movies and it's not due to some evil maliciousness that the hours are what they are, it's just a result of what you're trying to do.
While I think it's good to push back against Hollywood, that's not what Dwayne is doing by agreeing to a contract with certain hours and then showing up late. If he wanted to push back, then he wouldn't agree to that kind of contract or he would demand certain concessions, not just for him, but for everyone. In the article they also mention trying to work around him requiring 3 hours of workout every day, so they have shown that they would be willing to do that kind of stuff.