True. Historians also face the problem that all primary source evidence was created by and mediated through human beings with unique perspectives, beliefs, and worldviews. Trouillot also discusses the ways that people can simultaneously be participants in and narrators of events.
Since all of our evidence comes through accounts left behind by people, can we ever find an objective answer to the question of "what happened" or are we forced to always work in the realm of "that which was said to have happened"?