I usually hesitate to assign motives to the other side of any debate and the documentary stopped short of doing so. It's usually just an exercise in building a straw man and often is incorrect. I know that evolutionists are nearly always wrong about the motives of creationists and intelligent design supporters.
However, I’ll make some observations, anyway. I think you hit the nail on the head as to why the most vocal of the evolutionists reject ID. Suggesting God is real means submitting to the Creator and changing their lifestyle. For others, it’s a matter of pride (not wanting to be looked upon as stupid by their peers). And for some, it’s a matter of money (in the form of research grants). Pride and money are probably the biggest reasons for ID supporters being expelled at most universities.
Some know evolution cannot stand up to serious scrutiny. I’ve always thought that if you give a fool enough rope, he will hang himself. They claim we are fools, but won’t give us rope, because they know that the emperor is naked. It was interesting to read about a
professor recently that said his university fully supported hosting controversial speakers, but when the Discovery Institute took him up on the offer,
he refused.
Most evos are not being deceitful. They truly believe that ID does not use scientific principles. They think that if ID is allowed a foot in the door, scientific research will stop. They ignore that many great scientists (Newton, Mendel, etc.) were creationists, and it didn't stop them from doing research. (Many present day
scientists and
physicians also doubt evolution.)
They honestly believe that ID supporters do not do any
peer-reviewed research (Of course, as the movie pointed out, it's difficult to get an article published if the author and editor know they will be punished) and that ID is not
falsifiable (
another link). They don’t understand the difference between
operations science and historical science. They see examples of genetics and incorrectly extrapolate that into neo-Darwinian evolution.
Some think the only motivation of creationists is to get creationism taught in schools. None of the major creationists organizations (ICR, AIG) want that. Honestly, if they did teach creation in schools, the schools would probably get it wrong. Most creationists simply want students to understand the evidence
against evolution, too. Even most
liberals agree with that position. Churches should be teaching creation (sadly few actually equip believers to defend creation).
The more honest evolutionists recognize the shortcomings of evolution, but choose to deny the obvious. Francis Crick (discovered DNA) said, “Biologists must constantly keep in mind that what they see was not designed, but rather evolved.” Stephen Jay Gould recognized the problem with the Cambrian explosion. Scientists know there are holes in the theory of evolution for their particular discipline, but since the other disciplines (supposedly) support evolution, they overlook the red flags.
Polls have consistently shown that only 15% of the American public does not believe in evolution as it is taught in school. (More
Britons believe in evolution, but still less than half.) Of course, science should not be determined by public opinion. But when you have such a poor track record, it’s time for scientists to swallow their pride, step back, and honestly re-evaluate the facts.