There is a large section of the US who are permanently mired in a bi-polar view of politics and ideology, that every opinion you hold is either liberal or conservative, and this documentary is saying that there is no "open" debate occurring on University campuses (i.e. that conservative views are not being represented).
It is something of a cliché that academia is a left-leaning institution, but critical thinking should not attract spurious accusations of anti-conservative bias.
Critical thinking involves questioning authority, which does not lend itself well to conservative dogma. I'm sure that conservatives (ideological conservatives) would bitch that there should be an open debate, where Christian myths, imperial apologists and pro-lifers can juxtapose their views against what they consider "liberal" thought (everybody who does subscribe to the facile myths that most of middle America does). The examples used in this amateur documentary are extremely spurious, so called "conservatives" control the most powerful institutions within the US. The fact that every University in the US does not teach flag-waving pro-war bile is not evidence of a liberal conspiracy.
Its easy to accuse everyone of being "liberal" if you are born wealthy, white and middle-class. Young people question the moral authority of their elders because they are young, stop seeing it as a politically correct bias/liberal bias.
What would a conservative education actually look like? Young people who accept every myth of American exceptionalism and hoot like rednecks whenever another nation is invaded in the name of "freedom". The world is 6000 years old. Iraq has something to do with 9/11. Etc.
Go start your own schools in the desert, an apt setting for your barren mentality.