Sasha Weiss offers a deeper analysis:
Beyoncé’s performance makes us nervous when juxtaposed with the earnest idealism of the inauguration. It is an event that Americans rightfully take pride in: a peaceful transfer of power; a chance to re-affirm the values of openness, freedom of speech, and egalitarianism that define us; a democratic ceremony symbolically attended by all citizens. Beyoncé’s fakery, it seems, implies some larger fakery at the heart of the whole enterprise. But, of course, the ceremony is itself a performance—how else can we explain that it is through the recitation of scripted words in a ritual call-and-response that the President assumes his position of power? We don’t want to be reminded that we’re watching mere mortals who might trip on their way to the podium, stutter through the oaths of office, shiver in the cold, or worse, err in judgment and lead the country on the wrong path. These are the people we are entrusting to enact America’s timeless values? Too bad. Beyoncé reminded us. [...]
It’s not the fiction of Beyoncé’s performance that angers us, but the fear that underneath the pomp and idealism our political leaders are con men, telling us a story about ourselves that may not be true.