The final aerial shot is not of modern day Kingsbridge. Kingsbridge and its cathedral are entirely fictional. The shot is of modern-day Salisbury with a CGI cathedral combining elements of Salisbury Cathedral and Wells Cathedral which were the two cathedrals which inspired Follett during the writing of the novel.
Throughout the series, Stephen and Matilda are both referred to as "Majesty". English kings and queens did not use the title "Majesty" until the middle of the 16th century, nearly 400 years after the setting of this series