Did anyone actually survive the collapse?
Yes, two men survived who were inside the building and effectively "rode" the debris as it collapsed, cocooning them in relative safety. Their names are John McLoughlin and Will Jimeno and they are the focus of Stone's World Trade Center. I don't know how people here got it in their heads that the film was some all encompassing portrayal of the whole day, but I assure you it's not. I don't think this film will be riddled with bunk conspiracy like JFK, because these men are alive and contributed to the making of the film.