About far more than conservative vs. liberal.
I'm not gonna go off on a long tangent here, I'm pressed for time. The message in this film is similar to messages found in novels like The Giver as well as Anthem by Ayn Rand (who is, btw, considered a promoter of conservative ideologies). It's just allegorical. It's about nonconformity/individualism vs. conformity and narrrow-mindedness, in a general sense. I can see how people liken that to liberalism vs. conservatism, but seriously people, open your minds up past the small box of American political diatribes. There's a whole world of philisophical ideologies out there. Not just two. I know conservatives who agree with the film's promotion of individualist values. So, step outside your boxes and see it for what it is.
Also....Back to the Future is conservative? You...seriously think so?