The final battle was the entire point of the movie. In order to get to the final scene Captain Algren had to be surrounded by stupid ... and he's not too bright either.
No the final Battle was the entire point you got out of the movie. Which is fine.
When I watch an Edward Zwick movie like Glory I wasn't like... "Oh actually the battle of James Island was more of a skirmish and didn't play out in film with a prolonged melee," Or that the entire point of the film was the suicide charge up the slopes of Fort Wagner in the end.
Or like with Courage Under Fire. "Watched Courage Under Fire Today. The Tank Battle was unrealistic. Basically a star vehicle for Denzel Washington. Entire point of the film was Meg Ryan getting napalmed. 2/10."
I guess I got far more out of the film then you did.