Mostly to make a point; more people are likely to care about it not being okay if it's phrased that way. (Something, something, toxic masculinity, "suck it up tough guy, can't handle a little pat-down?")

The fact that the TSA agent a woman doesn't automatically make someone else comfortable with whatever liberties the agent feels like taking. It's still likely worse if it's a man doing it, but sharing a gender isn't an excuse for the agent to do whatever they want.