It actually came far closer in the battle scene than some imagine. There were a LOT of made-up elements. His friends... guns were basically wrong.
But the battle scene and his 'trials and tribulations' with the USA are not far off.
It was, of course, made as a propaganda picture on the eve of WW2. So there was a lot of 'American exceptionalism' and messages that "Killing is ok with the lord."
But it's not as bad as it could have been.
York was a real hero. The extra 'story' of his C/O status was not lost on the folks making movies to support a coming war against Germany. Also, the SecState at the time was the TN Senator Cordell Hull. And he was not going to let his state go un-recognized and the "Volunteer State" moniker was important to the war effort.
Also no 'accident' that the movie about Audie Murphy (To Hell and Back) emphasized his poor upbringing and shooting quail in the head with a .22 to feed his family as a scrawny under-sized kid. Back then, Propaganda was all about making America Great. Not destroying it in a race war.
To Hell and Back was also relatively accurate in what Murphy 'Did.' But many of the characters and situations outside the battlefield were designed to motivate and rally the American People. Not to be a documentary.
Sirhr
PS. Love both movies!