I believe that a documentary could be shown from both sides. It’s very informative to know both sides of the argument. I sincerely believe that both sides should be looked at in some way or another. However like writing a paper, the idea is to present an argument. This does not mean the filmmaker should lie, manipulate, or BS the truth. It should be shown as honest as possible while presenting the filmmaker’s version of the truth. That way the documentary isn’t only informative, but it serves a purpose. It also makes it more compelling.
If we were going to do a documentary about bears then it would be boring if it was just like “Here are bears!!”? Instead you want to show what the bears do. The bears have to have reason and purpose. It can be done like a story or informative, but it needs to be compelling. It may seem like a documentary shouldn’t cater to an audience, but if it doesn’t you run the risk of there being no audience. Then what would be the point of shooting the documentary?
So therefore a truthful subjective documentary that touches on the other side would be ideal. If you have an audience in mind you can cater to them, but be honest and don’t patronize them. Take the audience on a trip into your mind and how you feel about a subject, but be sure to do it in a way that respects the other side and their beliefs.