The problem is when people take the historical accounts seriously. Is it even supposed to be accurate? It's after all based on a graphic novel.
I wonder why the film came out at a time when the neo-conservatives are pushing for a war against Iran. Was it a coincidence?
The 1962 version was more accurate. Take a look at
Iran Politics Club: 300 Spartans, The Real Story - Historically Accurate Review - Ahreeman X
Another critical article:
Bright Lights Film Journal | 300 Lies?