'No narrative is unbiased'=artful dodging

Yes, seeing as human beings aren't machines there may be no such thing as a documentary or narrative that is 100% objective, but the "No narrative is unbiased" argument is more often than not the fallback argument of a liar who has been found out. Bias comes in degrees, and a relatively less biased narrative is more trustworthy than a more biased one. I know this sounds painfully elementary, but people like that weaselly art critic don't seem to get it, or probably deliberately chose not too. Really, Marla's easily flustered dad ultimately seemed far less sleazy than the smirking cultural commentators who wanted to reduce the whole Marla story to competing narratives.