Well if you’re going to blame someone, blame Frank Miller, not Hollywood. He’s the one who wrote it, long before it was ever considered for a film. Personally, I’d rather blame Hollywood as I’m no fan of the “movie machine” out there, but in this instance it really has nothing to do with “them”.
I believe the term used to describe 300 in an interview back in 1998 was “historically inspired”, not “based on”, but I have no idea where to find that article now. I think it was in Wizard magazine, but I’m really not sure. In other words, it was meant to be a fantasy, because Frank Miller writes comic books. I don’t think the intent was to piss on any graves.
In that regards though, any realistic based-on-actual-fact war movie could be construed as pissing on someone‘s grave, depending on whose perspective the story was done from.
I just don’t understand the furor over this particular film. It was written as a fantasy and is obviously depicted as a fantasy as well. If it wasn’t so obviously a work of fiction, I could understand the controversy a bit more since the Persians were portrayed quite beastly, but the addition of the mythical factors should serve to separate the film from any type of comparison against reality.
If Vietnam came out with a movie called 77, inspired by Khe Sanh, and it had giant orangutangs and other mythical beasts, I really don’t think I’d be offended and I had actual relatives that died there.