Hollywood has to appeal to the broadest audience, and when it comes to most social and economic issues, America is progressive. Because of that, the messages that are in Hollywood movies tend to be, for instance, pro-environment.
The only way that Hollywood ever skews toward liberal is because part of what we make out of Hollywood involves writers, actors, directors, musicians, set designers, and photographers. In general, people like that are going to be more progressive, more open minded, a little more altruistic.
Obamacare is a private mandate that will drive billions to the insurance industry, much like the auto insurance mandate. Hardly socialism. In fact, it was a Republican plan to begin with.