To be fair to the screenwriter, he did apologize about it later saying that the film had been deliberately targeted to an American audience and that it was not something he would do again. There were other complaints made about the film as well (such as it depicting U-Boat crew firing on the survivors, something that actually only happened once in the U-Boat ranks) but, in fairness to those, that's no worse than how many British movies depicted them for years.
I think this might be part of the problem, some movies are being made about 'movies', for example, it will be interesting to see how Peter Jackson deals with the double-legacy of Dambusters, which has a history not only as a factual event, but also as a far more fictional one as depicted in the movie of the same name. Apparently every effort is being made to be historically accurate, so it will be interesting to see how it is received.