I agree with you. As I said in my last post, some subjects simply cannot be defined objectively, and history is certainly one of them. One thing I can recall from my own high school history days is a teacher who gave an assignment to the class to compare the descriptions of the American Revolution as written in the Encyclopedia Americana with that written in the Encyclopedia Brittanica. For the most part the facts were in agreement. The way they were presented, and interpreted, were miles apart much of the time.
But this doesn't mean they cannot be taught in a more neutral manner, without bias. Using a consensus of historians to prepare a history text book rather than an extremely biased local BOE would tend to give a much more realistic view of actual events, while still allowing those events to be presented in context.