"it’s just as clear that his delusions were inflated, if not created, by the entertainment industry he grew up in."

That wording made it seem to me like she was saying there was a chance that they created the delusions but they at least inflated them.

She also wrote: "no one should be surprised when those impulses take luridly literal form in the culture at large."

You're trying to downplay her screed but it was a horrible piece of writing and one that does a disservice to the points you're trying to make. Using the act of a madman to try to point out the influence Hollywood can have over everybody is a waste of breath and distasteful IMO.