Firstly, great topic
My view: “Never let the facts get in the way of a good story.”
I’m a history buff myself, but I’m also a film buff. I can of course only speak for myself, but those two things mean a) if I want the 100% historically accurate version, I will pick up a history book, and b) if the film is well made, entertaining, and doesn’t ignorantly spit on the graves of the real people involved, I forgive historical inaccuracies.
I agree with Attrage. Most of us here have the ability to differentiate between historical fact and fiction, so we can compartmentalize inaccuracies in movies while still appreciating the overall product. The problem is the large number of people who have no concept of history, accepting the movie versions as completely factual.
I think of Patton
as an example. How many of us (even those who know better) hear George C. Scott's voice when we think of Patton? The few newsreels I have seen of Patton actually speaking show him to have a somewhat high and reedy voice. If it weren't for those newsreels, Patton will forever be thought of as having the booming delivery shown in the movie. Once all the WWII generation have passed on, no one will remember Patton's real voice.
I have another example of perceptual drift, that comes from one of my other hobbies. For years, I restored old British sports cars (MGs mostly). The MGB series originally came with a shield-shaped badge on the front grille which showed the MG Octagon in bas relief, etched out from the back side and painted internally. This gave the logo a sense of depth. These badges are subject to cracking and fading over time, so they are usually replaced when the car is restored. The large aftermarket British parts suppliers began marketing a cheap and cheesy Chinese-made badge that used a flat version of the logo. For about 15 years now, that is the ONLY type of replacement that can be found new. What will eventually happen is you will see all restored cars with the flat badge, and people will think that's the way they came from the Factory. If substandard imitation exists for long enough, it begins to supplant the real thing.